Iran says fourth round of nuclear talks with US 'postponed'

A fourth round of talks between the United States and Iran, which was due to take place in Rome on Saturday, have been postponed and a new date will be set "depending on the U.S. approach", a senior Iranian official told Reuters on Thursday.

"U.S. sanctions on Iran during the nuclear talks are not helping the sides to resolve the nuclear dispute through diplomacy," the official told Reuters. "Depending on the U.S. approach, the date of the next round of talks will be announced".

Earlier, Iran accused the U.S. of "contradictory behavior and provocative statements" after Washington warned Tehran of consequences for backing Yemen's Houthis and imposed new oil-related sanctions on it in the midst of nuclear talks.

Oman, which mediated earlier sessions of U.S.-Iran talks, said on Thursday that the next round of the nuclear discussions provisionally planned for May 3 would be rescheduled for logistical reasons.

Separately, Iran's foreign ministry spokesperson said Tehran will continue to engage "seriously and resolutely" in result-oriented negotiations with the U.S., state media reported.

Washington and Tehran have been conducting negotiations over the past month on a deal to curb Iran's nuclear program in return for the lifting of financial sanctions.

On Wednesday Washington imposed sanctions on entities it accused of involvement in the illicit trade of Iranian oil and petrochemicals.

Separately, U.S. Defense Secretary Pete Hegseth warned Iran that it would face consequences for supporting the Houthis, who control northern Yemen and have attacked ships in the Red Sea in what the group says is solidarity with the Palestinians.

Washington has been bombing the Houthis intensively since mid-March, hitting more than 1,000 targets. Tehran says the Houthis act independently.

Iran's Foreign Ministry spokesperson Esmaeil Baghaei criticized "the contradictory approach of American decision-makers and their lack of goodwill and seriousness in advancing the path of diplomacy", state media reported.

"The responsibility for the consequences and destructive effects of the contradictory behavior and provocative statements of American officials regarding Iran will lie with the American side," Baghaei said.

U.S. President Donald Trump, who abandoned an earlier nuclear deal between world powers and Iran during his first term in 2018, has threatened to attack Iran unless it agrees a new deal. Both sides have so far described the previous rounds of talks, held weekly and mediated by Oman, as productive.