(Sharecast News) - Oil prices slumped amid fresh hopes for US-Iran negotiations after Donald Trump said talks would resume on Monday.

At 0740 BST, Brent crude was down 5.7% at $82.96 a barrel, while West Texas Intermediate was 6.5% lower a $79.21.

Prices fell back as Donald Trump said talks with Iran will begin on Monday after the US refrained from carrying out new strikes against Tehran over the weekend.

The US President said on Truth Social that at the request of Iran and other Middle Eastern countries, he held off on the biggest attack "since World War II", "subject to being able to rapidly make a deal". A deal would include the "immediate, complete, and total opening of the Hormuz Strait, and an end to Iran's nuclear threat," Trump said.

Speaking to reporters on Air Force One on Sunday, he said: "They knew the extent of the attack because they saw it forming.

"We're talking to them in the form of a negotiation. It begins tomorrow afternoon."

Iranian media denied that Tehran had asked for the strikes to be called off, while Iran's foreign ministry said it was not in discussions with the US but rather talking to Oman about establishing a temporary safe route through the Hormuz Strait.

Rabobank said: "Obviously we've heard this one before. Iran's Fars news agency reports that 'informed sources' deny that any agreement has been reached on the status of the Strait of Hormuz, and that policy regarding the critical shipping route remains unchanged."

Russ Mould, investment director at AJ Bell, was also cautious. "The market has been here before and a more concerted fall in crude and in government bond yields will require greater evidence that a lasting resolution can be forthcoming this time round," he said.