I. Introduction

As Figure 1 shows, the Strait of Hormuz, a vital maritime choke point for global energy trade, has experienced ongoing geopolitical and economic disruption since 28 February 2026, following joint military strikes by the US and Israel on Iran, which included the killing of Iran’s supreme leader Ali Khamenei. In response, Iran launched retaliatory drone and missile attacks on US military bases, Israeli territory and other Gulf states, while its Islamic Revolutionary Guard Corps (IRGC) issued warnings prohibiting vessel or ship passage through the strait, leading to an effective halt in shipping traffic.

Figure 1: Map of the Strait of Hormuz (source: http://www.drishticuet.com)

The warnings and subsequent attacks on ships caused a sharp decline in maritime transit, with tanker traffic declining first by approximately 70% and over 150 vessels anchoring outside the Strait to avoid risks, and soon traffic went to about zero, as Figure 2 shows. [1]

Figure 2: Traffic through the Strait of Hormuz has dropped following US-Israeli attacks on Iran on February 28, 2026 (source: Clarksons Research & Guardian)

This disruption affected approximately 20% of the world’s daily oil supply and significant volumes of liquefied natural gas (LNG), prompting major shipping firms to suspend operations in the area. Oil and gas prices surged, with Brent crude oil rising to US $126 per barrel at its peak, amid fears of prolonged supply shortages that could push prices toward $100 per barrel. Crude oil prices surpassed $100 per barrel on 8 March 2026 for the first time in four years and then fell. However, as Iran’s new supreme leader, Mojtaba Khamenei, said that the Strait of Hormuz should remain closed and that Iran will continue attacks on its Persian Gulf neighbors, Brent crude oil price jumped back above $100 per barrel on 12 March 2026, as Figure 3 shows.

Then when the US and Iran agreed to a conditional two-week ceasefire on April 8, Brent crude oil price dropped under $ 100 per barrel.

Iran and the US agreed to a conditional two-week ceasefire, during which shipping traffic will be allowed through the Strait of Hormuz, but the Strait of Hormuz was not reopened.

The US and Iran had high stakes talks in Islamabad, Pakistani capital on April 12, but failed to reach a truce deal.

Figure 3: Brent crude oil price, 2026 (Source: Trading Economics)

With the de facto closure of the Strait of Hormuz by Iran under way, US President Donald Trump’s planned naval blockade of Iran would further cripple international shipping, exacerbating the energy crisis, as Figure 4 shows. Energy analysts warn that Trump’s planned naval blockade of Iran sends shock waves across global energy markets,

Brent crude oil price surged above $100 a barrel once again on April 13, 2026, after Trump announced that the US Navy would blockade the Strait of Hormuz and “interdict every vessel in international waters that has paid a toll to Iran” (See Figure 3).

With this information in background, this paper analyzes the impacts of double blockage of the Strait of Hormuz by Iran as well as the US on global oil prices. In doing so, this paper first explains the importance of the Strait of Hormuz by examining volumes of oil flows through the Strait of Hormuz. And then the paper examines how much the double blockage of the Strait of Hormuz by Iran as well as the US will affect global oil price.

Figure 4: US blockage of Strait of Hormuz (source: marineregions.org & BBC)

II. The Importance of Strait of Hormuz

International energy markets depend on reliable transport routes. The blockage of oil transit through a major chokepoint, even temporarily, can lead to substantial supply delays and higher shipping costs, thereby resulting in higher world energy prices. Although most chokepoints can be circumvented by using other routes – which adds significantly to transit time – some chokepoints have no practical alternatives.

The world’s most important chokepoints by volume of oil transit are the Strait of Hormuz, leading out of the Persian Gulf, and the Strait of Malacca, which links the Indian and Pacific Oceans (see Figure 5).

In the first half of 2025 (1H25), total world petroleum and other liquids supply was about 104.4 million barrels per day. It is estimated that about 76% of that amount (79.8 million barrels per day) traveled via seaborne trade. [2]

Figure 5: The world’s most important maritime oil chokepoints (source: EIA)

As Table 1 shows, in the first half of 2025, 20.9 million barrels per day of crude oil and petroleum liquids passed through the Strait of Hormuz – nearly 25 % of seaborne-traded oil worldwide, according to the US Energy Information Administration (EIA). Only the Strait of Malacca, with 23.2 million barrels per day, moved more crude oil and petroleum liquids in the first half of 2025 than the Strait of Hormuz.

Among 20.9 million barrels per day of crude oil and petroleum liquids passed through the strait of Hormuz, 14.7 million barrels per day were crude oil and condensates, while 6.1 million barrels per day were petroleum products, as Table 2 shows.

Table 1: Volume of crude oil and petroleum liquids transported through world chokepoints, 2020-first half 2025(1H25)

Table 2: Volume of crude oil, condensate, and petroleum products transported through the Strait of Hormuz, 2020–1H25

If the Strait of Hormuz were to be closed, alternatives that exist could move only a portion of the oil volumes out of the Strait.

Pipelines in Saudi Arabia, the UAE, and Iran provide alternatives to the Strait of Hormuz (see Figure 6, 7, 8). Saudi Aramco’s East-West crude oil pipeline and the UAE’s Abu Dhabi pipeline together could provide about 4.7 million barrels per day of capacity to bypass the Strait in the event of a supply disruption. By 2027, the UAE plans to build another 1.5 million barrels per day pipeline circumventing the Strait, from the Jebel Dhanna export terminal to Fujairah. Iran inaugurated the Goreh-Jask oil pipeline and the Jask oil export terminal on the Gulf of Oman with a single export cargo in 2021, and it sent a few small loadings in late 2024. The pipeline’s effective capacity remains around 0.3 million barrels per day. [3]

Figure 6. Map of the Strait of Hormuz and its alternative routes (source: EIA)

Figure 7: Saudi Aramco’s East-West crude oil pipeline (source: http://www.firstonline.info)

Figure 8: UAE ADCOP pipeline (source: Energy news beat)

As Figure 9 shows, Saudi Arabia moved more crude oil and condensate through the Strait of Hormuz than any other country, and Iraq and UAE followed Saudi Arabia. Around 0.3 million barrels per day of intra-Saudi Arabia volumes transited the Strait in 2023 from Saudi ports in the Persian Gulf, most notably Ras Tanura, to Saudi ports in the Red Sea. Red Sea attacks and oil disruptions in the Bab el-Mandeb Strait that began at the end of 2023 caused these intra-Saudi Arabia volumes to drop to 18,000 barrels per day by the first half of 2025.

Figure 9: Volume of crude oil and condensate transported through the Strait of Hormuz, 2020–1H25

US Energy Information Administration estimates that 89% of the crude oil and condensate that moved through the Strait of Hormuz went to Asian markets in the first half of 2025. China, India, Japan, and South Korea were the top destinations, accounting for a combined 74% of all Hormuz crude oil and condensate flows in the first half of 2025.

III. The Impacts of double blockage of the Strait of Hormuz on global oil price

1. How will US blockade of the Strait of Hormuz work?

Since the outbreak of the Iran-US war on April 28, 2026, Iran has effectively blockaded and controlled the Strait of Hormuz, a key passage for global energy trade. As shown in Figure 10, maritime traffic through the Strait of Hormuz has dropped to near zero due to Iran’s threats and subsequent attacks by the Iranian Revolutionary Guard on ships actually navigating the strait.

In particular, the passage of oil tankers (light blue) transporting crude oil has almost ceased in March 2026 compared to February.

Figure 10: Traffic through the Strait of Hormuz, February, March, April 2026 (source: IMF Portwatch & Statista)

Under this situation, the blockade order would apply to all Iranian ports, both inside and outside the Strait from 10 am ET (Eastern Time) Monday, US Central Command (CENTCOM) said. Iran has had a chokehold on the Strait, a critical passage for the global energy trade, since the Iran War broke out.

Trump indicated that US mission would have an even wider scope, possibly well outside the Persian Gulf.

“I have also instructed our Navy to seek and interdict every vessel in International Waters that has paid a toll to Iran. No one who pays an illegal toll will have safe passage on the high seas,” he said on Sunday, referring to Iran’s move to charge ships for safe passage.

The point of the mission is to maximize pressure on Iran by strangling its cashflow from the energy trade. But solving the global energy crisis stemming from this Iran War will take another tough job: clearing any sea mines Iran has laid.

The missions mark a shift in this Iran War, from the skies to the sea. To date, the war has been mostly conducted by air, although a US submarine did sink an Iranian navy frigate off Sri Lanka in the early days of the war.

While US Navy aircraft flying off aircraft carriers have also been involved. But those missions aren’t as complex, or as risky, as what Trump is asking of the Navy now.

Here’s a look at what’s involved. As Figure 11 shows, US military blockade on Iranian ports takes effect: All of Iran’s ports along the Gulf are subject to a US blockade, with US Central Command saying the blockade will be enforced “against vessels of all countries entering or departing Iranian ports and coastal areas.” Iran’s Islamic Revolutionary Guard Corps warned that “no port in the Persian Gulf and the Sea of Oman will be safe” if its own ports are threatened, according to Iranian state media. [4]

Figure 11: US military blockade on Iranian ports takes effect (source: CNN & National Geospatial-Intelligence Agency)

2. Can the US effectively pull the blockage off?

Closing off Iran’s ports, almost all of which are inside the Persian Gulf from the Strait of Hormuz, to oil tankers and other merchant vessels would be “procedurally difficult but practical if the US has maritime superiority,” said analyst Carl Schuster, a former US Navy captain. [5]

And that may not be the case.

Iran still has the capability of fighting back with mines, an unknown number of small boats that can carry missiles, surface drones, aerial drones and land-based cruise missiles as well as shoulder-fired anti-aircraft missiles that could target helicopters and fighter jets protecting the ships in the water, analysts say.

Jihoon Yu, a research fellow at the Korea Institute for Defense Analyses and a former South Korean submarine officer, called the US blockade as a “high risk” because of those Iranian options to strike back. [6]

“If Iran accepts it as a violation of its sovereignty or a de facto expansion of maritime warfare, the possibility of a local military conflict could increase,” Yu said.

James Stavridis, a retired US Navy admiral, told CNN’s Fareed Zakaria show that the Pentagon would need two aircraft carrier strike groups and about a dozen surface ships outside the Gulf to patrol the Strait of Hormuz at its entrance. [7]

Inside the Gulf, Stavridis said, at least six US destroyers would be needed, along with help from the navies of US partners such as Saudi Arabia and the United Arab Emirates.

“You want to try to bottle it up on both sides,” he said of the Strait.

Schuster said that the US Navy trains boarding teams of about 10 to 14 people to take control of merchant ships and vessels. Each team includes an “officer of the deck,” who essentially acts as the merchant ship’s captain after a takeover and “guides it to an anchorage or port for detainment.” [8]

Schuster said that of six US destroyers inside the Strait of Hormuz, two would be used to do boardings, with the other four nearby to deal with any Iranian attempts to stop those actions. The two destroyers could possibly seize six ships a day between them, Schuster said.

3. The Impacts of double blockage of the Strait of Hormuz on global oil price

a. Will a double blockage of the Strait of Hormuz make global oil price skyrocket?

US blockade of the Strait of Hormuz would worsen global energy crisis, energy analysts say. While US military says it will blockade Iranian ports only, such move would have ripples worldwide, according to analysts.

US President Donald Trump’s planned naval blockade of Iran would further cripple international shipping, thereby exacerbating the energy crisis roiling the global economy, analysts warned.

Global oil prices surged above $100 a barrel on Monday April 13, 2026, after Trump announced that the US Navy would blockade the Strait of Hormuz and “interdict every vessel in international waters that has paid a toll to Iran.”

Trita Parsi, co-founder of the Quincy Institute for Responsible Statecraft, said that a US blockade would have a cascading impact across the global economy.

“Anything that currently takes more oil off the energy market will push prices up, which in turn will push gas prices further,” Parsi told Al Jazeera. [9]

Oil could soar above $150 a barrel if the blockade were to trigger retaliation from the Iran-aligned Houthis in Yemen, who could shut down Bab al-Mandeb, a strait that connects the Red Sea to the Gulf of Aden and Indian Ocean, Parsi said.

The Trump administration last month announced it would waive some sanctions on Iranian oil exports to help ease the global energy crunch.

Iran has essentially closed the Strait since the beginning of the US-Iran war on February 28, allowing only a small number of ships to transit after vetting and authorization.

About 3,200 vessels and ships were stranded west of the Strait due to the blockage as of Saturday, according to the maritime intelligence company ‘Windward.’

Anas Alhajji, former chief economist at NGP Energy Capital Management, said that the Trump administration’s blockade of the Iranian ports is an actual blockade of the Strait of Hormuz,” Alhajji told Al Jazeera. [10]

The resulting rise in gas and oil prices would also cause the cost of fertilizers, chemicals, and raw materials used to make plastics to increase, according to analysts.

Cameron Johnson, a senior partner at the Shanghai-based supply chain consultancy Tidalwave Solutions, said that she expects prices of many raw materials to rise within several weeks if President Trump makes good on his blockade threat.

“The wild card really is the time frame on this,” Johnson told Al Jazeera.

“If this is a negotiating tactic – remember we still have eight or nine days left of the ceasefire – then it might not really matter. But if this prolongs itself to the end of April and into the first week of May, you will see prices all over the world spike for raw materials, including crude oil.” [11]

Chad Norville, president of the oil and gas industry news site Rigzone, said that Trump’s threat is a further blow to confidence in the situation in the Strait of Hormuz ever returning to normal.

The threat alone is likely to push up insurance premiums for shipping and logistics companies and reduce the volume of trade passing the Strait each day, he said.

“Disruptions to shipping and elevated risk in the Gulf region were already well established due to the Iran war,” Norville told Al Jazeera. [12]

“This threat doesn’t create that baseline. It amplifies it by reinforcing uncertainty around one of the world’s most important chokepoints.”

b. Analysis

On February 18, 2026, Clayton Seigle of the US think tank CSIS presented the following four scenarios regarding oil supply disruptions and rising international oil prices resulting from an armed conflict between the US and Iran. [13]

Scenario 1: Iranian disruption of oil shipments from Gulf states; Scenario 2: Attacks on Iranian oil facilities by the US or Israel; Scenario 3: Direct attacks by Iran on oil facilities in Gulf states; Scenario 4: Blocking of Iranian crude oil shipments by the US or Israel.

In Scenario 4, the US (or in conjunction with Israel) could blockade Iran’s Kharg Island, a key facility for loading Iranian crude oil for export, or seizing oil tankers transporting Iranian crude.

This could cause a disruption of up to 1.6 million barrels per day in Iranian crude oil exports, all of which is destined for China. However, because crude oil is a globally exchangeable commodity, a supply disruption in any one location affects global crude oil prices. If Iranian crude oil supplies are cut off by a US attack or blockage, China will set out to secure alternative oil, which is highly likely to raise international crude oil prices by at least $10 to $12. Of course, this scenario could change at any time. That is, the US (or Israel) could lift sanctions on Iranian crude oil shipments at any moment, and Iran’s crude oil exports could recover without permanent damage. This is similar to the phenomenon observed after the US blockaded Venezuelan crude oil shipments. However, actual crude oil prices could remain high for a longer period due to insurance premiums and rising premiums caused by war risks.

Currently, the US blockade of the Strait of Hormuz implies a situation where, in addition to blockade of Iranian crude oil exports by the US in Clayton Seigle’s Scenario 4, there is a blockade of crude oil exports from other Gulf states attempting to pass through the Strait by paying tolls to Iran. Therefore, the current double blockade situation surrounding the Strait of Hormuz is similar to a scenario where Clayton Seigle’s Scenario 1 (Iran’s disruption of oil shipments from Gulf states) and Scenario 4 (the blockade of Iranian crude oil shipments by the US) occur simultaneously. Seigle argued that under Scenario 1, the supply of crude oil and refined petroleum products from non-Iranian Gulf states could decrease or be temporarily suspended by up to 18 million barrels per day. He claimed that in such case, international oil prices could rise by $30, from the then $60 range to the $90 range.

Seigle also argued that under Scenario 4, Iranian crude oil exports could be disrupted by up to 1.6 million barrels per day. He asserted that if the supply of Iranian crude oil is cut off by a US attack or blockade, China would move to secure alternative crude oil, which is highly likely to raise international crude oil prices by at least $10 to $12. Therefore, under the double blockade scenario surrounding the Strait of Hormuz, it can be simply calculated that international oil prices could rise by approximately $40 per barrel – a $30 increase under Scenario 1 plus an increase of about $10 under Scenario 4.

However, realistically, it remains uncertain whether international oil prices will rise from the current level of $95–$100 per barrel to $140 per barrel according to these scenarios. How international oil prices settle will largely depend on the ongoing ceasefire and peace negotiations between the US and Iran.

In fact, on Friday April 17, 2026, Iran said it fully reopened the Strait of Hormuz to commercial vessels for the remainder of the US-brokered 10-day truce that was agreed on Thursday between Israel and Lebanon, but threatened to close it again if the US kept in place its blockade of Iranian ships and ports. Following Iran’s Friday announcement about the reopening of the Strait of Hormuz, WTI price dropped 9.4% to settle at $82.59 per barrel, while Brent crude, the international standard, fell 9.1% to settle at $90.38 per barrel.

However, on April 18, 2026, Iran once again closed the Strait of Hormuz, criticizing US blockade of Iranian ships and ports. Brent crude futures surged nearly 7% to above $96 per barrel on April 20, reversing losses from the previous session as geopolitical tensions flared again in the Strait of Hormuz.

Figure 12: Brent crude futures (source: Trading Economics)

Iran has threatened that if the US continues its blockade of the Strait of Hormuz, it will make the Houthi rebels blockade the Red Sea and the Bab el-Mandeb Strait at its entrance, which are used for crude oil shipments from Saudi Arabia, the United Arab Emirates, Russia, and other countries, by bypassing the Strait of Hormuz. If the Red Sea and the Bab el-Mandeb Strait are blockaded, international oil prices could rise to $150–$200 per barrel.

How international oil prices settle also depends on the availability of alternative shipping routes to export crude oil by bypassing the Strait of Hormuz, which will be explained below.

c. Alternative Transport Routes Bypassing the Strait of Hormuz and their Limitations

Figure 13: Alternatives to the Strait of Hormuz (source: IEA)

As Figure 13 shows, there are alternatives to the Strait of Hormuz. [14] However, available capacity for alternative export routes is limited. Only Saudi Arabia and the UAE have operational crude pipelines that could potentially re-route flows to bypass the Strait of Hormuz, with an estimated 3.5 to 5.5 million barrels per day of available capacity. While additional capacity may exist in major pipelines to bypass the Strait, the logistics and supply chains needed to re-route and export substantial flows have not been robustly tested.

Saudi Arabia – the Abqaiq-Yanbu pipeline system (East-West Crude Pipeline) crosses Saudi Arabia, connecting Abqaiq to Yanbu on the Red Sea. The system is composed of two lines with a total design capacity of 5 million barrels per day of crude oil. In March 2025, Aramco reported that it had increased capacity to 7 million barrels per day, but sustainable flows have not been tested at this level. As of early 2026, it is estimated that about 2 million barrels per day of the pipeline’s capacity is used, leaving between 3 and 5 million barrels per day of spare capacity, depending on operational conditions and available export capacity on the Saudi West Coast.

UAE – the Abu Dhabi Crude Oil Pipeline (ADCOP) runs 400 km from onshore oil facilities at Habshan to Fujairah. The original nameplate capacity of the line is 1.5 million barrels per day with a reported current capacity close to 1.8 million barrels per day. The UAE exports around 1.1 million barrels per day of domestic crude via this route, leaving room for up to 700 thousand barrels per day of additional volumes in the case of a Strait closure.

Iran – the Jask oil terminal was officially inaugurated in 2021 to transport crude oil from the Goreh-Jask pipeline to Jask on the Gulf of Oman. The pipeline has a reported capacity of 1 million barrels per day. However, the pipeline and port effectively remain non-operational. A test load was exported from Jask in late 2024, but no further oil has been exported from Jask since then. The terminal is currently not considered a viable crude export option for Iranian crude oil.

IV. Conclusion

This paper analyzed the impacts of double blockage of the Strait of Hormuz by Iran as well as the US on global oil prices. In doing so, this paper first explained the importance of the Strait of Hormuz by examining volumes of oil flows through the Strait of Hormuz. And then the paper examined how much the double blockage of the Strait of Hormuz by Iran as well as the US will affect global oil price.

This paper claimed that the current double blockade situation surrounding the Strait of Hormuz is similar to a scenario where Clayton Seigle’s Scenario 1 (Iran’s disruption of oil shipments from Gulf states) and Scenario 4 (the blockade of Iranian crude oil shipments by the US or Israel) occur simultaneously.

Therefore, under the double blockade scenario, it can be simply calculated that international oil prices could rise by approximately $40 per barrel – a $30 increase under Scenario 1 plus an increase of about $10 under Scenario 4.

In addition, this paper argued that if the Red Sea and the Bab el-Mandeb Strait are blockaded by the Houthis, international oil prices could rise to $150–$200 per barrel under double blockage of the Strait of Hormuz.