Muscat (Oman), Apr 26 (AP) Iran and the United States held in-depth negotiations in Oman over Tehran's rapidly advancing nuclear programme on Saturday, talks that likely will hinge on the Islamic Republic's enrichment of uranium.

The talks ran for several hours in Muscat, the mountain-wrapped capital of this sultanate on the eastern edge of the Arabian Peninsula.

A person close to Steve Witkoff, the US special envoy to the Middle East, acknowledged that the meeting had started and later ended.

The source spoke on condition of anonymity to discuss the closed-door talks. Iranian state television also reported their conclusion.

However, neither Iranian Foreign Minister Abbas Araghchi nor Witkoff offered any immediate specifics or details on the talks that they'll lead.

But Omani Foreign Minister Badr al-Busaidi, who has mediated the two previous round of talks in Muscat and Rome, offered a positive note at the end of Saturday's negotiations.

Iran and the US “identified a shared aspiration to reach agreement based on mutual respect and enduring commitments,” al-Busaidi posted on X. “Core principles, objectives and technical concerns were all addressed. Talks will continue next week with a further high level meeting provisionally scheduled for May 3.” Araghchi arrived Friday in Oman and visited the Muscat International Book Fair, surrounded by television cameras and photojournalists. Video late Saturday morning showed Araghchi heading to the talks.

Witkoff was in Moscow on Friday meeting with Russian President Vladimir Putin. He arrived Saturday to Oman.

Meanwhile Saturday, a major explosion rocked a port in southern Iran just after the talks began, killing four people and injuring more than 500 others. Authorities offered no immediate cause for the blast, which appeared to have been caused by a highly combustible material — though officials ruled out its oil and gas industry.

Nuclear talks come after decades of tensions The talks seek to limit Iran's nuclear programme in exchange for the lifting of some of the crushing economic sanctions the US has imposed on the Islamic Republic closing in on a half-century of enmity.

US President Donald Trump has repeatedly threatened to unleash airstrikes targeting Iran's programme if a deal isn't reached. Iranian officials increasingly warn that they could pursue a nuclear weapon with their stockpile of uranium enriched to near weapons-grade levels.

Iran's 2015 nuclear deal with world powers did limit Tehran's programme. However, Trump unilaterally withdrew from it in 2018, setting in motion years of attacks and tensions. The wider Middle East also remains on edge over the Israel-Hamas war in the Gaza Strip.

Trump, travelling to Rome for the funeral of Pope Francis, again said that he hoped negotiations would lead to a new nuclear deal. However, he still held out the possibility of a military strike if they didn't.

“The Iran situation is coming out very well,” Trump said on Air Force One. “We've had a lot of talks with them and I think we're going to have a deal. I'd much rather have a deal than the other alternative. That would be good for humanity.” He added: “There are some people that want to make a different kind of a deal — a much nastier deal — and I don't want that to happen to Iran if we can avoid it.” Talks turn to experts While Araghchi and Witkoff were again expected to speak through the Omanis, experts on both sides also will begin negotiating details of a possible deal.

From the Iranian side, Iranian Deputy Foreign Minister Majid Takht-e Ravanchi will lead Tehran's expert team, said Mohammad Golzari, an Iranian government official. Takht-e Ravanchi took part in the 2015 nuclear talks.

The US technical team will be led by Michael Anton, the director of US Secretary of State Marco Rubio's policy planning staff. Anton doesn't have the nuclear policy experience of those who led Washington's efforts in the 2015 talks.

Iran has insisted that keeping its enrichment is key. But Witkoff has muddied the issue by first suggesting in a television interview that Iran could enrich uranium at 3.67 per cent, then later saying that all enrichment must stop.

The demand that all enrichment stop also has been repeated by Rubio.

However, Iranians remain hopeful that the talks could be successful, as the Iranian Rial has rebounded from historic lows during which it took more than 1 million Rials to buy USD 1.

“It's OK to negotiate, to make the nuclear programme smaller or bigger, and reach a deal,” Tehran resident Farzin Keivan said. “Of course we shouldn't give them everything. After all, we've suffered a lot for this programme.” (AP) NPK NPK