A United States blockade of Iranian ports at the Strait of Hormuz could inflict economic damage of up to $435 million, or ₹4,081 crore, per day as tensions between Washington and Tehran intensify, according to a report in the Wall Street Journal, according to a NDTV report.

The blockade, announced by President Donald Trump as beginning on Monday, is expected to disrupt the flow of oil, fertiliser, food and other goods, fuelling inflation inside Iran.

Analysts caution that the scale of Iran’s losses will depend on several uncertain factors, including how effectively the US Navy enforces the blockade and whether Tehran can divert exports through the Jask terminal, which lies outside Hormuz waters.

In the short term, the impact may be softened by Iranian oil already at sea. As of late March, Iran had an estimated 154 million barrels floating outside the blockade-affected Gulf, according to data from Kpler.

Miad Maleki, a former official with the US Treasury Department’s Office of Foreign Assets Control, told the Wall Street Journal that the quarantine of Iran’s ports would cost about $435 million daily. His estimates include around $276 million in lost exports, primarily crude oil and petrochemicals.

These calculations assume Iran exports 1.5 million barrels of oil per day at a wartime price of $87 per barrel, with more than 90 per cent of shipments transiting through Kharg Island in the Persian Gulf.

President Trump threatened to impose the blockade after talks aimed at extending a fragile ceasefire collapsed over the weekend. Iran had previously restricted tanker traffic through the Strait of Hormuz, permitting only vessels deemed friendly to pass, while charging significant fees. The blockade is designed to maximise pressure on Tehran by choking off its energy trade revenues.

Marc Thiessen, columnist and former White House Director of Speechwriting, argued that the blockade achieves much the same effect as a military operation to seize Kharg Island, through which most of Iran’s oil passes.

He noted that the blockade could cripple Iran’s oil exports and energy income without the risks associated with deploying US ground forces. By obstructing energy exports to China, which receives 45 to 50 per cent of its crude oil and 30 per cent of its liquefied natural gas imports via the strait, Trump could also increase pressure on Beijing to align with Washington’s campaign.

Enforcing the blockade will demand a sustained commitment of US Navy ships and personnel, alongside clear guidance from the Trump administration and the Navy’s legal department, according to the Associated Press.

The US currently has 16 warships stationed in the Middle East, but none in the Persian Gulf, which forms most of Iran’s coastline. A notice to mariners has stated that access to Iranian ports is restricted, though details of how these measures will be applied remain under development.

The greatest challenge for US forces lies in the sheer volume of shipping traffic through the Strait of Hormuz, where nearly 20 per cent of the world’s traded oil passes during peacetime.

Naval power expert Sidharth Kaushal of the Royal United Services Institute in London observed that a significant number of vessels may be required to enforce restrictions.

He added that much depends on the early days of the blockade—how many ships the US can seize and how effectively it can deter others from attempting to slip through. Nonetheless, Kaushal concluded that it will likely prove difficult for the US to enforce the blockade fully.

NDTV