Iran halts the blockade of the Strait of Ormuz. What does that mean?

Monday's strike on American bases in Iraq and Qatar – although it was stopped by missile defense systems – again revealed how quickly local escalation could threaten global energy security. At the heart of these tensions is the blockade of the Strait of Ormuz – through which flows nearly 20% of the world's oil volume. Why did Tehran refrain from this step? What are the consequences for Europe and Poland?

Suspended response, halted escalation

Although it has only been two days since the Iranian attack on American bases, the tension around the Persian Gulf has not weakened. As already indicated in the previous textThe escalation in this area has direct consequences for us, too. So it is time to look at this situation from the perspective of European energy security – including Poland – especially in the context of the potential blockade of the Ormuz Strait.

The lack of an immediate, offensive response from the United States following the Iranian attack of June 23 was crucial for the continuation of the crisis. President Donald Trump, despite earlier announcements of "ready to respond decisively", decided to limit US action to defensive measures and calls for deescalation. According to the Department of Defense's communications, neither Al Udeid in Qatar nor Ain al-Assad's Iraq base suffered serious damage, which allowed Washington to react in a balanced manner.

It was this protective step of the President of the United States that may have proved decisive in stopping the spiral of consequences that the blockade of such a strategic shipping route as the Strait of Ormuz is. Although the Iranian parliament voted out symbolic actions to block the Strait, the lack of direct retaliation from the United States allowed the authorities in Tehran to stop the implementation of this decision. As a result, despite the increase in tension and international pressure, the Strait of Ormuz – recognised as a sensitive hub for world trade in energy resources – remains open.

Trail weight – a scale that acts like a detonator

According to Energy Information Administration, 21 million barrels of oil and condensate per day (EIA, 2024) were transported by the Ormuz Strait in 2024, which corresponds to nearly one fifth of world trade in this raw material by sea. The closure of this shipping route would mean a supply gap six times the daily extraction from Norway – one of the main oil exporters in Europe.

However, not only the physical shortage of raw material raises market concerns. Equally important is the risk premium – according to calculations Lloyd’s Letter, insurance premium type war-risk for VLCC tankers increased within 24 hours from the Iranian attack by 65% (Lloyd’s Letter, June 24, 2025). In the event of disturbance, some of the cargo could be diverted through the Saudi East-West (7 million b/d) or Habshan-Fujajra pipelines in the UAE (1.5 million b/d), however, which would generate high logistical costs. Higher freight rates and insurance premiums could translate into an increase in delivery costs also to terminals in Gdańsk and Naftoport.

A blockade that also hits Iran

The closure of the Ormuz Strait would have global effects – it is obvious. However, it is worth noting that the consequences of such a decision also reach the sources themselves – in this case, oil producers from the Gulf region. Interrupting the export trail would not only hit the main recipients of the raw material, primarily Asian countries including China. This would also affect exporters – Iraq, Kuwait and, above all, Saudi Arabia. One cannot forget that the Ormuz Strait also flows natural gas from Qatar and oil produced by... Iran itself.

And here is the paradox of this strategy – an economic blow to the world would be a blow to self-interest. Iranian oil would not reach the audience, and Tehran would have suffered financially as much as its opponents. That's why the Ormuz blockade is an escalation agent with high cost also for the user, but expensive also for the user. Called the "nuclear option", it remains in Iran's arsenal as a deterrent – powerful but used as a last resort.

Ormuz Strait in Iranian deterrence strategy

Iran has a full array of measures that allow it to block the Ormuz Strait in a short time. A key 38-kilometre section of the transit route could be mined in a few hours, resulting from the deployment of the Marine Revolutionary Guard Corps mobile units and the operational readiness of the Fast Attack Craft fleet, whose tactics are based on swarming action and surprise strikes. An additional element of the deterrence system remains the land-based anti-shipper missiles Ghadir and Noor, also deployed on islands located within the strait. Such infrastructure creates an important barrier to both physical and operational maritime transit.

However, even the most effective blockade has serious side effects. Iran continues to export around 1.3 million barrels of oil per day in various forms and channels. Blocking the strait would also mean breaking this revenue stream, which would pose a serious risk to the stability of the regime in the face of growing economic difficulties. Therefore, the blockade of Ormuz is an extreme weapon for Iran – strong in action, but expensive also for the user. As Dr. Ali Vaez of the International Crisis Group put it: "Blocada is an atomic weapon – it scares away more when it stays in a holster".

What does that mean? Iran halts the blockade of the Strait of Ormuz

Iran's decision not to close the Ormuz Strait – despite parliamentary discussions and internal and external pressures – is a clear signal of strategic restraint. Against the backdrop of Israel and the United States, Tehran strives to balance the need for a decisive response with calculation geopolitical costs. Leaving the Strait open allows the Iranian authorities to retain their face as a force capable of escalation, but at the same time ready to postpone confrontation. This attitude gives international energy markets a moment of breath, stabilising raw materials prices and reducing the risk of a regional explosion with global impacts.

This situation gives Washington and his partners time for diplomatic action and space to build a wider deterrence coalition. For Iran, the decision not to close the Ormuz Strait allows you to sustain tension and send a signal of readiness for escalation. However, such an extension of the crisis takes the effect of surprise. The blockade of the transit route remains the most serious tool of Tehran's pressure.

For Poland, where nearly 9% of imported oil comes from the Gulf region, any increase in Brent's price of $10 per barrel means an additional import cost of PLN 100 million per month.

Written by Mariusz Dasiewicz

• Middle East on the edge. Iran's war fleet and escalation scenarios
• Escalation and concentration of forces: Diego Garcia in the spotlight
• Is the US attack on Iran inevitable?