Why has Trump halted Iran attacks, and what is the deal he is hinting at?

United States President Donald Trump says the US and Israel have agreed to halt new attacks on Iran, provided a deal to end the months-long conflict is reached "rapidly".

Trump said on his Truth Social platform early on Sunday in Iran and late on Saturday in the US that Iran and other Middle Eastern countries asked him to hold off on the attacks because "the perimeters of a deal has been agreed to".

Iran denied Trump's claim that Tehran asked the US to refrain from conducting new strikes. Citing military officials, the agency said the allegation "was nothing but a new lie" and that the Iranian armed forces were "on high alert and ready for any eventuality".

Trump earlier said in his post that the US was "locked and loaded and ready to go against the Islamic Republic of Iran" but Tehran and other Middle Eastern countries asked him to hold off on new attacks.

"Based on this request, I have agreed, for the future benefit of the WORLD and, likewise, the survival of a successful and prosperous Iran, to cancel the attack, subject to being able to rapidly make a DEAL," Trump posted on his Truth Social platform.

He said the deal "would include the Immediate, Complete, and Total OPENING OF THE HORMUZ STRAIT, and an end to Iran's nuclear threat".

"The Country of Israel joins me in this commitment. Get to work, everybody, and get it DONE," he wrote in the post.

Meanwhile, the US news website Axios reported that Saudi Crown Prince Mohammed bin Salman (MBS) spoke with Trump on Saturday and expressed concern over his plans for large new attacks against Iran.

MBS reportedly urged Trump to de-escalate and refrain from launching the attacks.

Ross Harrison, a senior fellow at the Middle East Institute, told Al Jazeera that it remains difficult to identify a clear US strategy in the war on Iran because Trump has repeatedly signalled imminent escalation before pulling back.

"From the Iranian perspective, they probably will believe that Donald Trump blinked because of the potential risk of escalation," he said, adding that the latest announcement would not reflect a genuine de-escalation unless the US and Iran reached a clear agreement to reopen the Strait of Hormuz.

"Unless there's some kind of clear agreement on opening the strait and removing the blockade, this isn't going to hold. The announcement we saw is only going to be another pause," he added.