US Secretary of State Marco Rubio told the Senate Foreign Relations Committee on Tuesday that Iran had agreed to negotiate aspects of its nuclear programme it had previously refused to discuss, marking a tentative shift in Tehran's posture even as the broader US-Israeli conflict with Iran continues and a fragile ceasefire in Lebanon shows signs of collapse.

Appearing before the committee for the first time since the outbreak of the war with Iran, Rubio outlined specific conditions for any diplomatic progress. He said Iran must first clearly announce that the Strait of Hormuz — the narrow waterway between the Arabian Peninsula and Iran through which roughly a fifth of global oil supplies pass — is open, describing this as the first requirement in any talks. He added that Iran must commit to concrete negotiations on the disposition of its highly enriched uranium. Crucially, Rubio said the Trump administration had not offered sanctions relief simply in exchange for reopening the strait, stressing that any easing of economic pressure would be "conditions-based" and tied to progress on the nuclear file. "They have agreed to negotiate aspects of their nuclear programme that just a month ago, just a year ago, they were refusing to even mention," he said, while cautioning that this was "not a guarantee that ultimately it will lead to a deal that's acceptable."

The diplomatic picture was complicated earlier in the day when two semiofficial Iranian news agencies, Fars and Tasnim, reported that Tehran had suspended communications with mediators over Israel's continuing strikes in Lebanon. President Donald Trump pushed back on those reports in a social media post, insisting that conversations had been "going on continuously" and calling the Iranian reports "false and erroneous." Rubio also addressed the status of Iran's supreme leader, Mojtaba Khamenei, telling senators he was alive and "increasingly engaging," though all of his communications had been in writing and through intermediaries.

The hearing took place against a backdrop of significant regional turbulence. In Lebanon, a three-month war between Israel and Hezbollah has killed more than 3,400 people and displaced over 1.2 million. A deal brokered by Trump — under which Israel would refrain from striking Beirut's southern suburbs in exchange for Hezbollah halting attacks on northern Israel — appeared increasingly shaky, with Hezbollah publicly rejecting any "partial ceasefire." Separately, Trump was reported by Axios to have sharply confronted Israeli Prime Minister Benjamin Netanyahu by phone on Monday, with US officials saying he viewed the scale of Israeli military operations as disproportionate and feared they were undermining ongoing diplomacy with Iran.

The hearing also laid bare congressional frustration with the administration's conduct of the war. Democratic Senator Jeanne Shaheen, the committee's ranking member, accused the administration of bypassing Congress on major war-related decisions, while Republican committee chair James Risch noted unease among some members of his own party over limited oversight. Rubio is scheduled to testify before the House of Representatives later the same day, as scrutiny over the administration's Middle East strategy continues to mount.