BUERGENSTOCK — U.S. President Donald Trump on June 21 warned he could renew strikes on Iran even as Vice President J.D. Vance held the first talks with Iranian officials under a recently signed interim memorandum of understanding, in discussions overshadowed by Tehran’s announcement that it had again closed the Strait of Hormuz.
The Swiss meeting at the Buergenstock resort marked the initial implementation talks called for in the agreement, which envisages reopening the strait and halting hostilities, including in Lebanon where Israel launched an incursion in March. Iran said it shut the waterway because Washington had failed to secure a cessation of fighting in Lebanon and declared the June 21 talks would not move on to substantive topics such as its nuclear programme.
Trump, posting on social media, urged Tehran to “immediately stop their highly paid proxies in Lebanon” and threatened to hit Iran “very hard again,” referring to the country’s support for Hezbollah. U.S. media also quoted the president as warning Iranian officials that closing the strait could threaten Iran’s territorial integrity and that the United States might assert control over the waterway.
At the talks, held in the presence of Qatari mediators, Vance acknowledged the messy nature of such negotiations but said progress had been made toward ending hostilities in Lebanon and framed the U.S. approach as an attempt to “turn over a new leaf” with the Iranian people. Iran’s delegation kept a low-profile posture: Foreign Minister Abbas Araqchi briefly greeted Pakistani mediator Shehbaz Sharif but did not meet Vance directly, and Iranian officials later said the nuclear file was not discussed.
Commercial shipping data showed an immediate drop in traffic after Iran’s announcement that no new permits would be issued for transits, with just one small tanker broadcasting its position compared with dozens in recent days. Iranian state media cited military sources saying the closure would remain in force until further notice. U.S. officials disputed the closure, but the suspension echoed earlier months when disruptions to the Strait of Hormuz drove global energy markets.
The memorandum of understanding foresees a 60-day negotiating window to address core issues such as Iran’s nuclear programme in exchange for phased economic relief, including sanctions waivers and access to frozen assets. Iranian leaders have stressed they expect initial economic benefits before substantive talks begin.
On the ground in Lebanon, June 21 was comparatively quieter after recent heavy exchanges, though authorities reported casualties and continued work to remove unexploded ordnance dropped by Israeli aircraft. More than a million Lebanese civilians have been displaced since March’s cross-border fighting began, and southern towns showed signs of limited return amid displays of local support for Hezbollah.