Oman and Iran were reportedly holding talks Sunday to explore options for ensuring smooth passage through the Strait of Hormuz amid the ongoing war, officials in Muscat said.

According to the state-run Oman News Agency, representatives from the foreign ministries of both countries are discussing options for "ensuring unimpeded passage through the Strait of Hormuz under the current circumstances in the region."

The timing of the talks coincides with an ultimatum from U.S. President Donald Trump.

The U.S. leader has repeatedly issued – and delayed – an ultimatum for the key waterway to be reopened, as Iranian threats to attack commercial shipping have disrupted global oil and gas deliveries and dealt a blow to markets.

Last week, he postponed the ultimatum until April 6, after claiming productive talks were being held with Iran.

In an expletive-laden post Sunday, Trump said: "Tuesday will be Power Plant Day, and Bridge Day, all wrapped up in one, in Iran."

Around 20% of global oil trade passes through the Strait of Hormuz. Since the start of the war on Feb. 28, maritime traffic has been virtually at a standstill.

Iran's control, warnings of mines and drone attacks and the withdrawal of war-risk insurance have made passage nearly impossible for Western shipping companies. Hundreds of tankers, container ships and freighters are stuck in the region.

At its narrowest point, the strait is only about 33 kilometers (20.50 miles) wide. The territorial waters of Iran and Oman overlap completely and there is no neutral high-seas corridor. Iran claims control over the entire passage and is planning a toll system for transit.

Energy markets expert Amena Bakr wrote on X that since March 30, data analytics company Kpler has identified a strategic split of shipping routes into an "Oman route" and an "Iran route."