President Donald Trump said on Monday that the United States will restore its naval blockade of Iranian shipping and impose a 20 percent fee on all other cargo transiting the Strait of Hormuz, sharply escalating a dispute over control of the world’s most important oil corridor. Trump called the tax a payback for costs of guarding the waterway. It painted the United States as the strait’s protector, responsible for defending a volatile stretch of water. The fee would apply to all cargo moving through the strait. The fee would be imposed immediately, he said. The announcement, made in a Truth Social post and echoed in a Fox News interview, was apart from the blockade and general shipping traffic. Only Iranian ships and their customers would be barred from entering or leaving, Trump said, while other nations would keep open use of the strait. Almost one-fifth of the world’s energy exports passed through the Strait of Hormuz before the US-Israel-Iran war broke out. The narrow channel separates Iran from Oman and serves as the main sea passage out of the Gulf for most regional oil producers. The International Maritime Organisation responded within hours, saying under existing international law, passage through international straits must continue to be toll- and charge-free. Separately, a spokesman for the UN shipping agency said there is no legal basis to impose mandatory tolls solely for transiting a strait. That is a stance the Trump administration itself took weeks earlier. Secretary of State Marco Rubio said in June that that no country is allowed to impose tolls on an international waterway, comments he made at the time while criticising Iranian plans to levy similar fees. Oman formally told the IMO earlier this month it opposes transit fees in the strait, a position at odds with Iran, which has discussed a joint service fee arrangement with Muscat that some reports value at up to $40 billion a year. Trump’s declaration came after a dramatic escala