How Trump is blockading Iran's ports and ships in the Strait of Hormuz

The US Navy is blockading Iranian ports after talks between the two countries broke down over the weekend.

But it has prompted several questions about the crucial Strait of Hormuz, including why America would target a trade route it had been trying to force open, how the blockade would work and what it could mean for the global economy.

How did we get here?

A two-week ceasefire came into force on 7 April shortly after Donald Trump threatened to obliterate Iran's "whole civilisation" if it did not reopen the waterway, through which some 20% of the world's oil passes.

Iran war latest: Iran warns US over blockade

But an initial round of peace talks failed to reach an agreement and Tehran has repeatedly ignored the US president's demands. Iran instead began charging some ships a fee, reportedly equivalent to millions of dollars, to transit the strait.

The disruption has had a wide impact on global economies, sending energy prices soaring, hitting government borrowing and risking higher inflation.

How will the blockade work?

American forces were due to begin enforcing the blockade at 3pm UK time on Monday after the US president vowed to block "any and all ships from trying to enter, or leave" the strait.

US Central Command, or CENTCOM, later clarified that the policy would affect only maritime traffic entering and exiting Iranian ports and would be enforced "impartially" against vessels, including those on the Persian Gulf and the Gulf of Oman.

The exact terms of the blockade, and how it would be enforced, remain unclear but the US began mine-clearing efforts over the weekend and CENTCOM's commander, Admiral Brad Cooper, said US forces would begin the "process of establishing a new passage... to encourage the free flow of commerce".

What has been the response?

According to Sky News' Data and Forensics team, just a handful of vessels have so far made passage out of the strait, based on data from shipping analytics company Windward.

Iran said the US blockade amounted to "piracy" and warned any military vessels attempting to approach Hormuz would be considered in violation of its ceasefire deal with America and would receive a firm response.

China, which imports nearly a third of its oil through the strait, has condemned the blockade as "dangerous and irresponsible". And China's President Xi Jinping has called for the preservation of the international rule of law, warning that the world should not "revert to the law of the jungle".

Meanwhile, Qatar has opposed using key shipping routes "as a bargaining chip" in the conflict.

How will this affect energy prices?

Mukesh Sahdev, chief oil analyst at XAnalysts, believes the US should be able to withstand higher gas and oil prices better than Iran can weather a major blow to its export income.

But US attempts to reopen the Strait of Hormuz "won't be a quick fix", according to Sally Lockwood, Sky News correspondent in Dubai.

"The financial pain is being felt all around the world, from a jet fuel shortage in Europe... to millions of people who could be pushed towards hunger in parts of the world like Asia," she said.

Blockade is 'act of war'

Donald Trump's ultimate goal is to pressure Iran to end its effective closure of the strait, potentially lowering oil prices. But starting another blockade is an ​act of war, Michael Clarke, Sky News' defence and security analyst, says.

He believes many of Iran's own oil tankers are already physically outside the scope of the blockade and still capable of supplying China with its energy needs.

The blockade also creates serious risks for the global economy and for the current ceasefire, which is currently holding.

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Risks and rewards

Enforcing the blockade will be a complicated, "high-risk" and legally contentious, Andreas Krieg, a senior lecturer at King's College London's School of Security Studies, said.

He added that the US would need to identify, track, communicate with, divert and maybe even board vessels linked to Iranian ports, all while "operating in one of the most crowded and politically sensitive waterways in the world".

Meanwhile, an additional 32 million people could be pushed into poverty "under the worst-case scenario", according to a report by the United Nations Development Programme.

(c) Sky News 2026: How Trump is blockading Iran's ports and ships in the Strait of Hormuz