As 4th round of ‘difficult but useful’ nuclear talks end without agreement, US says it's ‘encouraged’ by outcome

The fourth round of nuclear talks between the U.S. and Iran concluded on Sunday without any apparent breakthrough on the outstanding issues. 

A clear area of contention is the issue of uranium enrichment, with the U.S. publicly expressing its demand that Iran not be permitted to engage in uranium enrichment as part of the deal, which Iran is adamant about its right to enrich. 

Iran's Foreign Minister Abbas Araghchi insisted that the Islamic Republic cannot compromise on the issue: “The topic of uranium enrichment, in our opinion, is not subject to discussion, it will continue. There can be no speculation on this topic. There may be some restrictions on the level or volume of [enrichment] to build confidence,” he told Iranian state television following the talks in Oman. 

“The blood of our nuclear scientists was shed for enrichment and cannot be compromised or negotiated,” he continued, referring to the past assassinations of Iranian nuclear engineers widely believed to have been carried out by Israel. 

Iran has accelerated its uranium enrichment since the U.S. withdrew from the Joint Comprehensive Plan of Action (JCPOA) in 2018, although reports from that time, show that Iran had already exceeded the 3.67% enrichment limit even under the 2015 deal.

The latest reports by the International Atomic Energy Agency (IAEA) indicate that Iran has enriched uranium up to at least 60% purity, and that it could reach 90% purity within a matter of days. 

Civilian nuclear energy and nuclear materials used for medical imaging do not require uranium to be enriched beyond the previous 3.67% purity limit. 

Trump’s special envoy to the Middle East, Steve Witkoff, who had previously appeared to accept Iranian enrichment, took a harder stance on Thursday, before the fourth round of talks, saying, “We’re never doing a JCPOA deal.” 

“They cannot have centrifuges. They have to downblend all of their fuel that they have there and send it to a far-away place,” Witkoff said last week in an interview with U.S. news outlet Breitbart. “An enrichment program can never exist in the state of Iran ever again. That’s our red line.” 

“If we can get them to voluntarily do that, that is the most permanent way to make sure that they never get a weapon,” he continued. 

A senior Iranian official accused the U.S. of being inconsistent in its messaging, according to a report by Reuters. “What the US says publicly differs from what is said in negotiations,” the official said on condition of anonymity. 

Araghchi made similar statements after the talks ended, telling Iranian TV that talks are progressing, while criticizing “contradictory positions” within the U.S. government. 

“The two sides now have a better understanding of each other's positions. We can characterize the talks today as moving forward,” Araghchi said, before noting that “contradictory positions taken by the US in the media is not acceptable to us as they do not help the negotiations.” 

Last Wednesday, before the announcement of a fourth round of talks, President Donald Trump said Iran’s uranium enrichment centrifuges have to go. 

In an interview with conservative talk show host Hugh Hewitt, Trump said, “There are only two alternatives there, blow them up nicely [in a deal] or blow them up viciously.” 

Continuation of the talks signals the preference on both sides for political resolution to the issue, rather than a military one. President Trump is visiting the Middle East this week, his first such trip to the region of his second term, where he is expected to announce significant progress on talks regarding a security deal with Saudi Arabia. 

The BBC cited “a senior U.S. official” as saying the U.S. is “encouraged” by the talks. 

Saying the talks lasted over three hours, the official said more discussions are needed on “technical elements.” 

"Agreement was reached to move forward with the talks to continue working through technical elements,” the official stated. “We are encouraged by today's outcome and look forward to our next meeting, which will happen in the near future.” 

Iran’s Ministry of Foreign Affairs spokesman Esmaeil Baqaei, agreed, saying the talks were “difficult but useful to better understand each other’s positions.” 

The fourth round of indirect Iran-U.S. negotiations is concluded; difficult but useful talks to better undetstand each other's positions and to find reasonable & realistic ways to address the differences. Next round will be coordinated and announced by Oman.

— Esmaeil Baqaei (@IRIMFA_SPOX) May 11, 2025

Talks resumed in Oman this past weekend after a break, when the fourth round of talks was delayed, with Iranian and Omani officials blaming the delay on “logistical reasons.”   

Iran is seeking sanctions relief, after decades of sanctions have crippled its economy. Araghchi told IRIB that sanctions relief “is the basis of negotiations.” He also stated that “An agreement has been reached between the two sides on this issue.” 

While not directly involved, the Israeli government is cautiously watching the negotiations with some trepidation. Israeli Foreign Minister Gideon Sa’ar on Sunday called for the dismantling of Iran’s uranium enrichment facilities. 

“The most dangerous regime must not be allowed to obtain the world’s most dangerous weapon,” Sa’ar stated. 

Omani Foreign Minister Badr Albusaidi said the fifth round of talks “will take place once both parties have consulted their leaderships.”