US Vice President JD Vance has set new conditions for a potential diplomatic resolution to the conflict with Iran, telling Reuters that Tehran must demonstrate its commitment to not developing nuclear weapons by changing its enrichment programme. He questioned why Iran would need 60 percent enriched fuel if it did not want a nuclear weapon, adding that a failure to build highly enriched fuel was a basic threshold issue.
His comments contrast with the harder line taken by other senior US officials. Secretary of State Marco Rubio, speaking to reporters in Athens, reiterated that "Iran cannot have a nuclear weapon, simple, period, end of story." He accused Iran of missing several opportunities to reach an agreement and claimed it had "lost complete control" of the Strait of Hormuz and that its economy was in "total and complete freefall."
President Donald Trump has warned that the war will end through either "the nice way or the not-so-nice way."
In Tehran, officials have questioned whether Washington genuinely wants negotiations as the conflict continues. Iran’s government, led by President Masoud Pezeshkian and Foreign Minister Abbas Araghchi, has been in contact with US officials, though Vance noted that "it’s not totally clear how their country makes decisions."
Simon Mabon, a professor of international relations at Lancaster University, told Al Jazeera that the prospect of Iran seeking a nuclear weapon has remained remote. He said Tehran’s negotiators are more concerned with sanctions, frozen Iranian assets, the US naval blockade and fighting across the region – issues he described as the main obstacles to a deal.
The International Atomic Energy Agency reported that Iran had enriched uranium to 60 percent, below the roughly 90 percent considered weapons-grade. In its May 2025 assessment, it found no credible indications of a structured nuclear programme.
Analysts say Vance’s wording leaves open questions about what nuclear restrictions Washington would accept, even as pressure on Tehran remains central to its approach.