WASHINGTON: The top US general said on Tuesday (Mar 10) that while Iran was fighting, it was not more formidable than Washington had thought, as the United States geared up for the most intense day of strikes against Iran in the war so far.

General Dan Caine, chairman of the Joint Chiefs of Staff, told reporters that the United States was carrying out strikes against Iranian mine-laying vessels and the Pentagon would look at a range of options if it was tasked with escorting ships through the Strait of Hormuz.

The war has effectively shut the Strait of Hormuz, a chokepoint for global oil and liquefied natural gas transport, leaving tankers unable to sail for more than a week and forcing producers to halt pumping as storage fills.

"I think they're fighting, and I respect that, but I don't think they're more formidable than what we thought," Caine said.

US President Donald Trump on Monday threatened to escalate the war with Iran if it blocked oil shipments from the Middle East, even as he predicted a quick end to the conflict.

During the press conference at the Pentagon, US Defense Secretary Pete Hegseth said the United States would carry out the most intense day of strikes against Iran on Tuesday.

Hegseth reiterated that this would not be an endless war and said Trump would decide when the US campaign would end.

The United States has carried out strikes against more than 5,000 targets in the first 10 days of the campaign, including against more than 50 naval ships, Caine said.