BUERGENSTOCK, Switzerland/DUBAI - U.S. Vice President JD Vance held peace talks with Iran at a Swiss resort on Sunday, overshadowed by Tehran saying it had shut the Strait of Hormuz and would not discuss nuclear issues because Washington had failed to halt fighting in Lebanon.

The talks were the first to be held under the terms of a memorandum of understanding agreed a week ago, which calls for the strait to be reopened and a halt to all hostilities, including in Lebanon, which U.S. ally Israel invaded in March.

But with scant sign of an end to fighting there, Iran said on Saturday it had again shut the strait, whose closure for nearly four months caused the biggest disruption of global energy supplies in history.

It also said there could be no start to the next phase of substantive negotiations, including over its nuclear programme, until Lebanon fighting ends and it receives promised economic benefits.

SHIP TRACKING DATA

U.S. officials have disputed that the strait is closed and said 55 merchant ships crossed it on Saturday. But on Sunday Iran's Fars news agency cited a military source as saying no new permits were being issued for ships to cross until further notice.

Commercially available tracking data suggested that Iran had indeed cut off the strait, with no crossings by ships that reported their positions - other than those serving Iranian ports - after Iran announced it was closed.

The Iranian and U.S. delegations at the talks initially met Qatari and Pakistani mediators on Sunday ahead of the four-way meetings due later in the afternoon.

Vance briefly appeared in front of travelling media as he, envoy Steve Witkoff and President Donald Trump's son-in-law Jared Kushner met Pakistani Prime Minister Shehbaz Sharif and Pakistan's Army Chief Field Marshal Asim Munir.

Warm greetings were exchanged, and Vance said "What's up man?" as he shook hands with Munir and hugged him. "My brother," Munir said as he reached out to Witkoff and embraced him.

CLOSURE OF STRAIT COULD REVERSE FALL IN OIL PRICE

As often the case with major developments potentially affecting the global economy during the war, the announcement that the strait was again shut took place on the weekend with markets closed, making it difficult to assess the impact.

U.S. President Donald Trump said he agreed last week's memorandum of understanding to avert a global economic depression from high oil prices caused by shutting the strait.

After the agreement was announced, oil prices tumbled to levels unseen since the war started on hope of a quick restoration of disrupted supplies. But if the strait stays shut that could be partially undone when markets reopen on Monday.

Iran's foreign ministry spokesperson, Esmail Baghaei, said Sunday's talks in the scenic Qatari-owned Swiss mountain resort of Buergenstock would last for just one day.

Since Washington had failed to guarantee a ceasefire in Lebanon, the talks would cover only the implementation of the memorandum itself and not the substantive issues foreseen for the next stage of negotiations, Baghaei said.

VANCE HOPES FOR PROGRESS

The memorandum foresees 60 days of talks on issues such as curbing Iran's nuclear programme in return for the lifting of international sanctions.

Raphael Grossi, head of the International Atomic Energy Agency which is likely to be called upon to verify any nuclear deal, was also in Switzerland for the talks.

Even before substantive talks begin, Iran expects to receive economic benefits, such as sanctions waivers and the unfreezing of blocked assets.

President Masoud Pezeshkian, quoted by Fars, expressed optimism that talks with the U.S. could provide a strong basis for economic growth. He said the first achievement of the negotiations was restoring access to some of Iran's financial resources.

Before his departure, Vance told reporters: "I think we're going to hopefully make progress on the nuclear issue, make progress on the Lebanon ceasefire issue."

Ceasefires have been repeatedly announced in Lebanon, most recently on Friday, but have had only limited impact so far on the fighting there, with more than a million people driven from their homes by Israel's invasion.

However, in a possibly positive sign on Sunday, Reuters journalists in southern Lebanon saw some of the heaviest traffic since the memorandum was signed, with residents returning to homes they had fled in the south. Some stood beside cars backed up on the highway and waved Hezbollah flags.

AUTHORITIES SAY 20 KILLED IN LEBANON ON SATURDAY

Reuters journalists in southern Lebanon also saw rescuers on Saturday carrying wounded at the sites of Israeli attacks, which have reduced swathes of Lebanese towns and villages to ruins of concrete rubble that residents say resemble the Gaza Strip.

Lebanese authorities say 20 people were killed on Saturday, but there were no immediate reports of major violence on Sunday morning.

The army said on Sunday that specialised units were still working to dismantle unexploded Israeli bombs weighing 1,000 and 2,000 pounds that had been dropped on southern towns.

Trump's memorandum to end the war, which he jointly launched alongside Israeli Prime Minister Benjamin Netanyahu in February, is deeply unpopular in Israel, which did not participate in the peace talks.

Netanyahu's government says it will not withdraw from a swathe of Lebanon it seized after Hezbollah fighters fired across the border into Israel in solidarity with Tehran.

NONE OF WAR OBJECTIVES ACHIEVED

After Trump and Netanyahu launched the war in February, they said their aims were to destroy Iran's nuclear programme, halt its ability to threaten neighbours with missiles and proxy forces, and make it easier for Iranians to topple the government.

None of those objectives has yet been achieved, although U.S. officials say they still expect a strong final agreement to prevent Iran from obtaining a nuclear weapon.

A poll by Israel's Hebrew University, provided to Reuters, showed about 92% of Israelis believe Iran benefited more than Israel from the joint Israeli-U.S. military campaign, while just 8% see Israel as having emerged victorious.

(Reporting by Reuters bureaus; Writing by William Maclean, John Kruzel, Clarence Fernandez and Peter Graff; Editing by William Mallard and David Holmes)

U.S. Vice President JD Vance meets with Pakistan's Prime Minister Shehbaz Sharif, during high-level talks aimed at advancing a deal to end the Middle East conflict, at the Buergenstock Resort Lake Lucerne, near Stansstad, Switzerland, June 21, 2026. REUTERS/Nathan Howard/Pool Nathan Howard Reuters

Minister of Foreign Affairs of Iran, Seyyed Abbas Araqchi, centre, at the Buergenstock resort in Obbuergen, near Lucerne, Switzerland, Sunday, June 20, 2026. URS FLUEELER/Pool via REUTERS URS FLUEELER Reuters

Pakistan's Prime Minister Muhammad Shehbaz Sharif gesture upon arriving at the Buergenstock luxury hotel complex overlooking Lake Lucerne, Switzerland, on June 21, 2026, ahead of high-level talks aimed at advancing a deal to end the Middle East conflict. Fabrice Coffrini/Pool via REUTERS Fabrice Coffrini Reuters

A building of the Buergenstock luxury hotel complex overlooking Lake Lucerne, Switzerland, on June 21, 2026, ahead of high-level talks aimed at advancing a deal to end the Middle East conflict. Fabrice Coffrini/Pool via REUTERS Fabrice Coffrini Reuters

Flags of Switzerland, the United States, Qatar, Pakistan and the local Swiss canton of Nidwalden are photographed at the Burgenstock luxury hotel complex overlooking Lake Lucerne, Switzerland, on June 21, 2026, ahead of high-level talks aimed at advancing a deal to end the Middle East conflict. Fabrice Coffrini/Pool via REUTERS Fabrice Coffrini Reuters

Copyright Reuters or USA Today Network via Reuters Connect.

This story was originally published June 21, 2026 at 6:58 AM.

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