The first round of talks between Iran and the US were cancelled on Thursday as continued fighting between Israel and Hezbollah threatened to derail the nascent peace agreement just hours after it was signed.
Talks were scheduled to be held in Switzerland on Friday to build on the memorandum of understanding aimed at ending the Iran war and reopening the Strait of Hormuz . The agreement kickstarted a 60-day period for the two sides to hammer out a final peace accord.
But in a last-minute announcement on Thursday, the White House said Vice-President JD Vance would not be travelling because the talks had "not been finalised".
"The logistics of these negotiations have never been simple or predictable. As of now, the vice-president is not departing tonight," a spokesperson said. "We look forward to beginning technical talks as soon as possible." Al-Mayadeen TV, which is close to Iran and Hezbollah , said Iran's negotiating team had cancelled the trip amid continued Israeli strikes in Lebanon in violation of the ceasefire.
Israel and Hezbollah later agreed to immediately halt attacks from 1300 GMT in a ceasefire deal brokered by Qatar and the US.
Israeli forces have kept up their attacks in the south in the hours since the signing of the MOU, which requires both Israel and Hezbollah to end hostilities. Hezbollah, which has said it would observe the ceasefire if Israel halts its strikes, has responded with retaliatory attacks.
Iran has demanded a ceasefire in Lebanon as a condition to signing the MOU and has threatened to cancel it if Israel does not end the conflict. Iranian officials have insisted that Israel will be required to fully withdraw from Lebanese territory in any final agreement with the US.
Iranian parliament speaker and chief negotiator Mohammad Bagher Ghalibaf threatened to "deliver a crushing response" if the agreement is violated.
"They were once slapped during the war; if they choose to go down the same path again, they will receive a much harder slap," he wrote on X.
Ghalibaf and Vance were due to join mediators Pakistan and Qatar in the Swiss resort of Burgenstock to start negotiations over Iran's nuclear programme. The head of the UN's nuclear watchdog, Rafael Grossi, was also expected to attend.
The Swiss foreign ministry confirmed on Friday that the talks had been postponed. "Switzerland remains ready to facilitate these talks. The relevant preparatory work at Burgenstock is continuing," it said on its website.
Israel carried out a wave of bombing in Lebanon overnight described by the country's state-run news agency as being one of the most intense yet. At least 21 people were killed and dozens of others injured in strikes in the south the Bekaa valley.
The Israeli military said four of its soldiers were killed by Hezbollah. The deaths triggered genocidal threats from Israel's extremist National Security Minister Itamar Ben-Gvir, who demanded that "all of Lebanon must burn".
French foreign minister Jean-Noel Barrot called on the US to exert "all necessary pressure" on Israel to end its attacks.
Israel's attacks in Lebanon have drawn public criticism from Trump in recent days, who has increased pressure on Netanyahu to end the offensive.
Vance on Thursday added to a growing war of words with a sharp rebuke to Israeli ministers' criticism of the deal.
"We expect a complete ceasefire on all fronts, including Lebanon, Hezbollah and Israel," Trump wrote on his Truth Social platform on Thursday.
The New Arab has approached the foreign ministries of Pakistan, Iran and Qatar, as well as the US State Department for comment.