Iranian media, citing the semi-official Tasnim news agency, reported that Tehran received the letter. One account said Iran had not responded as of Thursday, and the Guardian reports a reply is imminent. The Wall Street Journal reported that Vance wrote on President Donald Trump's instructions to restart negotiations and head off further US strikes. Trump told reporters on Wednesday that he authorized the contact, and said it was meant to assist Iran with "medical supplies and various things," without giving specifics. He has also threatened to resume airstrikes, and has said Washington is "in no hurry to end its war with Iran."

According to the Guardian, the letter was facilitated by Qatari mediation and proposes restarting diplomacy. Iran would commit to its nuclear programme at the start of a process leading to the opening of the Strait of Hormuz within seven days, in return for US sanctions relief. Another account says the letter concentrated on a framework for negotiations rather than specific terms. Separately, ANI reports that the Qatari side proposed shortening the implementation period of Iran's plan to open the strait from five days to two, and that an American delegation is expected to join Iranian officials for talks in Doha.

The Guardian says Washington chose Rezaei because it judges that decision-making power rests with those closest to the Islamic Revolutionary Guards Corps. It describes Vance as a sceptic about the war, and sees his return to negotiations as a sign the US has not abandoned diplomacy. Tehran trusts him marginally more than other American officials, the paper reports, but remains suspicious after a previous 14-point memorandum of understanding fell apart over unilateral US steps and Trump's opposition.

Iran's public conditions have not changed. Parliament Speaker and chief negotiator Mohammad Bagher Ghalibaf wrote on X that Iran's conditions "have been repeatedly and clearly stated to the mediators," and said "the carrot-and-stick approach has no effect on Iran." Some outlets noted he did not explicitly tie the remarks to Vance's letter. The Guardian reports he said Iran's seven conditions must be met first, including lifting sanctions, ending asset freezes and ending the war on all fronts, which would require an Israeli ceasefire in Lebanon. Another account lists an immediate end to the US naval blockade among them. Araghchi's own list included restoring oil waivers and releasing frozen funds held in Qatar. Supreme Leader Mojtaba Khamenei said earlier in the week that conditions must be met before the war can end.

Several sticking points remain. The Guardian reports Iran is reluctant to make upfront, irreversible commitments, such as exporting its highly enriched uranium stockpile to a third country, if US steps like lifting sanctions on oil exports can be reversed. Tehran is also resistant to the return of UN nuclear inspectors, fearing they might provide intelligence on the stockpile, and has proposed blending the stockpile down so it can no longer be used for a weapon. On guarantees, the Guardian says China is often mentioned as the only country of sufficient status to underwrite a deal. The Times of Israel, citing the Qatari newspaper Al-Araby Al-Jadeed, reported a breakthrough in indirect talks on preliminary measures covering the nuclear programme, shipping through Hormuz and financial incentives, with China and Russia expected to serve as guarantors.

Both sides have spoken of force. Iran's Armed Forces Chief of Staff, Major-General Ali Abdollahi, said Iran will respond to any attack with "immense force," and Araghchi said the armed forces are at the "highest level of readiness." The Guardian reports Iran has plans to strike US interests across the Gulf, including desalination plants, internet cables and electricity grids. It adds that a third US attack in two years would likely require targeting previously off-limits sites, and that Europe would not join. Senator Chris Murphy and some other Democratic officials have criticized the US plan for a renewed attack, with Murphy calling it "insane."

The war began in late February with US and Israeli bombing of Iran, which killed the former Supreme Leader, Ayatollah Ali Khamenei, and senior military commanders. Iran retaliated against Israel, US installations and Gulf states hosting American bases, and restricted shipping through the Strait of Hormuz, which carries roughly one-fifth of global oil consumption. Washington answered with a naval blockade of Iranian ports. Thousands have been killed, mostly Iranian civilians. The Guardian says hopes of averting a major new conflict after Tuesday's US midterm elections rest on Iran's response to the letter.