U.S. Vice President JD Vance speaks during a press briefing at the White House in Washington, D.C., U.S., June 18, 2026. | Photo Credit: Eric Lee

US Vice President JD Vance has cancelled his planned trip to Switzerland for the formal in-person signing of the memorandum of understanding (MoU) with Iran due to unresolved logistical issues surrounding the next phase of negotiations, CNN reported, citing a White House spokesperson.

The White House said technical talks between Washington and Tehran had yet to be finalised.

“As the Vice President said at his press conference, the plans for the upcoming technical talks have not been finalized, and the U.S. delegation has been prepared to depart at the first available opportunity. But the logistics of these negotiations have never been simple or predictable,” CNN quoted the White House spokesperson as saying.

“As of now the Vice President is not departing tonight. We will let you know as soon as we have a concrete update about next step. We look forward to beginning technical talks as soon as possible,” the spokesperson added.

Trump-Iran MoU signed amid hopes of ceasefire and Strait of Hormuz reopening

The development comes a day after US President Donald Trump and Iranian President Masoud Pezeshkian signed a 14-point MoU aimed at ending hostilities between the two countries, reopening the Strait of Hormuz and launching a 60-day process to negotiate a final agreement on sanctions relief and Iran’s nuclear programme.

The agreement is already facing early challenges.

At least three people were killed in Israeli air strikes in southern Lebanon on Thursday, Al Jazeera reported, citing Lebanese state media, despite the MoU calling for the immediate and permanent termination of military operations on all fronts, including Lebanon. Despite the strikes, Israel’s Ambassador Yechiel Leiter assured the world of Israel’s commitment to the deal.

“Israel remains committed to the ceasefire agreement reached between Israel, Lebanon and the US. If Hezbollah does not violate the agreement, it will be kept. Under all circumstances, Israel retains its right to respond to attacks against it and to thwart threats to its territory, citizens and soldiers,” he said.

Vance warns Israel as US pushes diplomatic caution

However, the US is playing the game cautiously. CNN reported that JD Vance issued a sharp warning to members of the Israeli government who have criticised Trump over the agreement with Iran.

“If I was in the Cabinet of the Israeli government, I might not be attacking the only powerful ally that I have anywhere left in the entire world,” Vance said.

Trump reaffirmed Washington’s commitment to the agreement and said the United States expects all parties to uphold a ceasefire.

“The United States is committed to PEACE, and we encourage everyone in the Middle East Region to maintain their commitment to allowing our negotiations to beautifully unfold. The Markets are loving what is happening with Oil Prices way down, and Stocks way up. We expect a complete Ceasefire on all fronts, including Lebanon, Hezbollah, and Israel. Thank you for your attention to this matter!” Trump wrote on Truth Social.

US outlines conditions as Iran signals hard stance on security concerns

Earlier, Vance strongly defended the agreement, describing it as a diplomatic achievement built on military gains already secured by Washington.

“We destroyed a substantial number of their ballistic missiles and their ballistic missile launchers themselves. The nuclear weapons program is destroyed. It is gone,” Vance told reporters at the White House.

The Vice President said the agreement was not a concession to Tehran and stressed that both sides retained the right to self-defence.

“Israel doesn’t give up the right of self-defence... The Iranians don’t give up the right of self-defence,” he said.

Vance also said the United States expects Iran to abandon efforts to develop missiles capable of threatening countries beyond the region and stop financing activities that destabilise the Middle East.

According to Vance, implementation of certain provisions has already begun. He said the US Navy facilitated the passage of more than a dozen commercial vessels to Iranian ports, allowing more than 12.5 million barrels of oil to move through the Strait of Hormuz on Wednesday night.

Meanwhile, Iranian officials have made it clear that their support for the agreement depends heavily on developments in Lebanon.

In an interview with Lebanon’s Al-Akhbar newspaper, Iranian Foreign Ministry spokesperson Ismail Baghaei said the memorandum requires guarantees of Lebanon’s sovereignty and territorial integrity, which Tehran interprets as requiring a complete Israeli withdrawal from Lebanese territory.

Baghaei warned that failure to fulfil those commitments would invalidate the agreement.

“In this case, the Memorandum of Understanding would be considered null and void. When the other party guarantees Lebanon’s sovereignty and territorial integrity, everything you mentioned constitutes a violation of this memorandum,” he said.

He added that Iran had consistently insisted that any end to the conflict must apply to all fronts.

“When we speak of ending the war, it must end on all fronts and completely. This has been the principled position of the Islamic Republic of Iran since the beginning of the negotiations, and we have emphasized it throughout the entire negotiation process,” Baghaei said.

He further argued that a lasting peace could not be achieved while parts of Lebanese territory remained under Israeli control.

“As long as the occupation continues, it can be said that the war is still ongoing and has not ended in its essence,” he said.

CNN also reported that Iran’s Parliament Speaker and chief negotiator Mohammad Bagher Ghalibaf warned Washington against imposing additional conditions during the negotiations.

“In the event of bad faith, breach of contract, and excessive demands by the opposing side, we have no hesitation in delivering a crushing response to the enemy,” Ghalibaf said in a post on X.

He added, “They were once slapped during the war; if they wish to tread that path again, they will receive an even harder slap.”

Iran’s Supreme Leader Ayatollah Seyyed Mojtaba Khamenei also confirmed that he had authorised the agreement while claiming that Trump had resorted to pressure and leverage “out of desperation” to secure the initial deal, according to CNN.

The coming weeks are expected to test whether the agreement can hold as negotiations move forward amid continuing tensions in Lebanon and lingering mistrust between Washington and Tehran.

Published on June 19, 2026