US President Donald Trump on Monday denied reports that the top US military officer had flagged the risks of a major operation against Iran, saying Washington would "easily" beat Tehran in any war.

US media reported that General Dan Caine, the chairman of the joint chiefs of staff, had warned of various risks associated with strikes against Iran including a long-term entanglement.

But Trump said on his Truth Social network that it was "100 percent incorrect" that Caine was "against us going to war with Iran."

"General Caine, like all of us, would like not to see War but, if a decision is made on going against Iran at a Military level, it is his opinion that it will be something easily won," Trump wrote.

"He has not spoken of not doing Iran, or even the fake limited strikes that I have been reading about, he only knows one thing, how to WIN and, if he is told to do so, he will be leading the pack."

The Washington Post said Caine had expressed concern at the White House and Pentagon that munition shortages and a lack of allied support could increase danger to US personnel.

And the Wall Street Journal said both the top general and other Pentagon officials have warned of risks such as US and allied casualties as well as the danger of US air defences being depleted if its forces strike Iran.

The Axios news outlet meanwhile said Caine had warned of the United States "becoming entangled in a prolonged conflict."

Trump's roving negotiator Steve Witkoff and son-in-law Jared Kushner had also been urging the president to hold off attacks and give diplomacy a chance, Axios said.

The US president however accused the media outlets of writing "incorrectly, and purposefully so."

"I am the one that makes the decision, I would rather have a Deal than not but, if we don't make a Deal, it will be a very bad day for that Country and, very sadly, its people," Trump added.

Trump, who ordered strikes on Iran's nuclear facilities last year, has repeatedly threatened Tehran with further military action if ongoing talks do not reach a replacement for the nuclear deal the US president tore up in 2018, during his first term in office.

Washington has deployed a massive military force to the Middle East, sending two aircraft carriers as well as more than a dozen other ships, a large number of warplanes and other assets to the region.

But negotiations are still set to continue, with a US official saying the next round of talks with Tehran would take place on Thursday.

Nonetheless, Iran vowed on Monday to retaliate "ferociously" against any attack from the United States.

Tehran's foreign ministry said any strike, even limited, "would be regarded as an act of aggression".

"And any state would react to an act of aggression... ferociously, so that's what we would do," ministry spokesman Esmaeil Baqaei said.

Iran has said it will be ready to deliver a draft proposal for an agreement on its nuclear programme to mediators in the coming days. Trump said on Thursday that Tehran had at most 15 days to make a deal.

Iran says its nuclear programme is for civilian use, but the West believes it is aimed at building an atomic bomb. (AFP)



Edited by Cecil Wong