The fourth round of nuclear negotiations between Washington and Tehran, originally slated for Saturday in Rome, has been delayed indefinitely, a senior Iranian official told Reuters on Thursday.

The official said a new date will be determined based on “the US approach.”

“U.S. sanctions on Iran during the nuclear talks are not helping the sides to resolve the nuclear dispute through diplomacy,” the official stated, signaling frustration with ongoing pressure from Washington.

Oman, which served as the mediator in the US-Iran discussions, attributed the delay to “logistical reasons” and confirmed that the May 3 meeting would be rescheduled.

A separate source familiar with the diplomatic developments noted that the US had not confirmed its participation in the Rome session. According to the source, the timing and location for the next round of talks remain undecided but are expected to be finalized soon.

Meanwhile, Iran leveled fresh accusations against the United States, condemning what it described as “contradictory behaviour and provocative statements” following new American sanctions and warnings regarding Iran’s backing of Yemen’s Houthi rebels.

Despite rising tensions, Iran’s Foreign Ministry spokesperson Esmaeil Baghaei told state media that Tehran remains committed to negotiations, saying it will engage “seriously and resolutely” in talks aimed at tangible outcomes.

Last week, after the third round of talks between the US and Iran, a US official told Axios that the talks “were positive and productive. There is still much to do, but further progress was made on getting to a deal.”

President Donald Trump has repeatedly said he prefers to solve the nuclear standoff with Iran through a deal, but has also not ruled out military action against Iran.

Two weeks ago, the US President said that, if military action is required to thwart Iran’s nuclear program, Israel will be involved and even lead the effort.

“With Iran, if it requires military, we’re going to have military. Israel will be the leader of that. But nobody leads us, we do what we want to do,” Trump told reporters at the Oval Office.

Asked what his deadline would be for Iran to reach a deal, the President replied, “I can’t really be specific, but when you start talks, you know if they’re going along well or not, and I would say the conclusion would be when I think they’re not going along well.”

On Sunday, Trump expressed optimism that a deal could be reached between the US and Iran on the Islamic Republic’s nuclear program.

“On the Iran situation, I think we’re doing very well. I think a deal is going to be made there. That’s going to happen. Pretty soon it’s going to happen,” Trump told reporters.

“We’ll have something without having to start dropping bombs all over the place,” he added.