The United States and Iran have begun talks in Switzerland over the implementation of Washington and Tehran's provisional peace agreement, the Qatari foreign ministry has announced.
In a statement, Qatar said that "specialised technical and expert working groups" had been formed to negotiate the terms of a final deal, aiming to address "all issues" covered by the memorandum of understanding signed last week.
Delegations from the Iran and the US, along with mediators from Qatar and Pakistan, had arrived in Bürgenstock in the Swiss canton of Nidwalden earlier on Sunday.
US Vice President JD Vance is part of the US delegation.
Speaking from the US military's Joint Base Andrews in Maryland before departing for Switzerland, Vance told reporters that he was "looking forward" to the talks.
"We're going to hopefully make progress on the nuclear issue, make progress on the Lebanon ceasefire issue — those are the two big things that I think we're going to be focused on," he said.
The meeting had initially been scheduled to take place on Friday, but Vance postponed his trip as tensions in the Middle East heightened over Israeli clashes with Lebanon.
Iran's military said on Saturday that it had closed the Strait of Hormuz due to Israeli strikes on southern Lebanon.
It said it had made the decision "in light of America's bad faith and blatant breach of the first clause of the war-ending memorandum of understanding, and in response to the relentless and continuous violation of the ceasefire by the Zionist regime in southern Lebanon".
US Central Command said the waterway remained open on Saturday, however.
"Safe passage through the international waterway remained intact today as 55 merchant ships transited, moving large amounts of cargo and more than 17 million barrels of oil to global markets," it said in a statement.
Israel and the Iran-backed militant group Hezbollah had agreed to a renewed ceasefire on Friday, but Israel launched a fresh wave of attacks on Saturday morning.
Strikes on Nabatieh in southern Lebanon killed 16 people and injured 12 more on Saturday, per the Lebanese civil defence agency.
Israel's military said it carried out the strikes in response to its forces coming under fire from more than 50 Hezbollah rockets in southern Lebanon overnight on Friday.
"Among the targets struck were rocket launch positions, weapons storage facilities, and command centers," it said of its strikes on Lebanon.
On Friday, Israel's national security minister called for "all of Lebanon" to "burn" after the Israeli military reported that four of its soldiers had been killed in combat in the country.
