ZURICH/DUBAI/WASHINGTON - A high-level Iranian team departed for Switzerland on Saturday for talks with the United States, Iranian state media reported, while U.S. Vice President JD Vance indicated he would set off soon for meetings that Pakistan said will begin on Sunday.

The Iranian delegation was led by chief negotiator Mohammad Baqer Qalibaf and included Foreign Minister Abbas Araqchi as well as senior security, central bank and oil officials, Iranian media said.

Hours earlier, Tehran's Islamic Revolutionary Guard Corps had declared the Strait of Hormuz shut, appearing to raise the stakes ahead of the talks as both sides seek to advance an interim deal brokered by Pakistan and signed on Wednesday by U.S. President Donald Trump and Iranian President Masoud Pezeshkian to end their almost four-month war.

The IRGC warned ships not to approach the waterway, a vital conduit for global oil and gas supplies whose closure Iran has used as leverage, citing what it called Israeli "crimes" in Lebanon and a U.S. violation of commitments to establish a ceasefire. It said vessels would be at risk if they approached.

U.S. Central Command, however, said that 55 merchant ships had transited the Strait on Saturday, moving large amounts of cargo and more than 17 million barrels of oil to global markets, and that U.S. forces would ensure the flow of ships continued.

Mohammad Mokhber, an adviser to Iranian Supreme Leader Ayatollah Mojtaba Khamenei, accused the U.S. on X of failing to implement the first clause of its 14-point interim deal with Iran, which includes a ceasefire "on all fronts", including Lebanon.

He said that, as long as the agreement was only on paper, the flow of Middle East energy would remain halted.

The Lebanon truce appeared fragile as Israeli forces and the Iran-backed militant group Hezbollah attacked each other.

MOMENTUM BUILDS FOR U.S.-IRAN TALKS IN SWITZERLAND

Iranian Foreign Ministry spokesperson Esmaeil Baghaei said Iran would press in Switzerland for a fulfilment of commitments, citing past failures by the other side to honour agreements.

Vance, in an interview with Fox News, said he was confident the ceasefire agreed in Washington's 14-point deal with Tehran would hold, and that he had seen no evidence that the strait was closed.

"I expect that I will leave sometime in the next couple of days, but you know it's always a delicate coordination dance and the diplomatic protocols," Vance said.

He added that U.S. negotiators Jared Kushner and Steve Witkoff had been in Switzerland "for a few hours, dealing with some of the technical elements of this negotiation".

"My understanding, talking to Jared and Steve this morning, is things are going well," he added.

One of the conditions for starting 60 days of U.S.-Iranian talks on Tehran's nuclear program and other issues is a halt to fighting in Lebanon.

However, Lebanese Civil Defence said that 20 people had been killed by Israeli strikes in Lebanon on Saturday, hours after a truce there took effect.

Israel said it was responding to attacks from Hezbollah, while the Iran-backed group said it would not allow Israel "freedom of movement" in Lebanon.

Israel, left out of the talks, says it is not party to the Iran-U.S. deal, and will keep its forces in the Lebanese territory it occupies.

A U.S. official had said the truce took effect at 4 p.m. (1300 GMT) on Friday, and Israeli and Hezbollah sources confirmed the agreement to Reuters.

The Israeli broadcaster Channel 12 reported that the prime minister and defence minister had instructed the military to hold fire in Lebanon, but that it would not withdraw from areas it had captured.

FIGHTING IN LEBANON CONTINUES

Lebanon's state news agency NNA said Israeli warplanes and drones had struck locations across southern Lebanon and the Bekaa Valley on Saturday, both Hezbollah strongholds.

An Israeli military official said Hezbollah fired more than 50 projectiles at Israeli forces in southern Lebanon overnight, and that Israel had attacked what it described as Hezbollah targets in response.

A military statement said Israel was committed to the ceasefire and would continue to act against any threat to Israel or its forces.

"All night we heard explosions. We got kind of excited by those statements about a ceasefire, but everything is continuing as usual," said Ofri Valfer, a resident of northern Israel.

"You can hear very loud blasts here, and life goes on alongside that. Hopefully better days will come."

Lebanon's health ministry says 4,057 people have been killed in Israeli attacks since March 2, including medics, women and children, though it does not specify how many of the dead were combatants.

Israeli authorities say at least 32 soldiers and four civilians have been killed in fighting with Hezbollah.

(Reporting by Reuters bureaus; Writing by William Maclean; Editing by Kevin Liffey)

Rescuers embrace as they work at the site of an Israeli air strike in Barish, Tyre district, Lebanon, June 20, 2026. Zohra Bensemra Reuters

A machine works at the site of an Israeli air strike on a house as rescuers try to recover bodies from under the rubble, in Barish, in Tyre district, Lebanon June 20, 2026. REUTERS/Zohra Bensemra Zohra Bensemra Reuters

Smoke billows from southern Lebanon following an Israeli strike, as seen from Nabatieh, Lebanon, June 20, 2026. REUTERS/Stringer Stringer Reuters

Iranian President Masoud Pezeshkian signs the document of U.S. Memorandum of Understanding in Tehran, Iran, June 18, 2026. Iran's Presidential website/WANA (West Asia News Agency)/Handout via REUTERS Iran's Presidential website/WANA Reuters

A woman walks near a mural depicting the late leader of the Islamic Revolution, Ayatollah Ruhollah Khomeini, and Iran's late Supreme Leader Ayatollah Ali Khamenei, on a street in Tehran, Iran, June 18, 2026. Majid Asgaripour/WANA (West Asia News Agency) via REUTERS Majid Asgaripour Reuters

Copyright Reuters or USA Today Network via Reuters Connect.

This story was originally published June 20, 2026 at 12:00 PM.

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