A direct three-way meeting between U.S., Iran and Pakistan began in Islamabad after progress in earlier indirect discussions, Pakistani government officials and Iran’s IRNA news agency said.
The face-to-face talks began after a reduction in Israeli strikes on southern Lebanon and other preconditions being met, the state-run news agency said.
According to Iranian media reports, the Iranian delegation decided to begin talks with their U.S. counterparts after meeting with their Pakistani host, Prime Minister Shehbaz Sharif, who also sat down with U.S. Vice President JD Vance.
The Iranian delegation is led by parliamentary speaker Mohammad Bagher Ghalibaf and Vance was accompanied by White House envoy Steve Witkoff and President Donald Trump's son-in-law Jared Kushner.
"Commending the commitment of both delegations to engage constructively, the Prime Minister expressed the hope that these talks would serve as a stepping stone toward durable peace in the region," Sharif's office said.
Iran has previously said that any agreement on a permanent end to fighting must include the unfreezing of sanctioned Iranian assets as well as an end to Israel's war against Hezbollah in Lebanon, which Vance has said will not be up for discussion in Islamabad.
But Iranian state television's correspondent at the talks said he understood that progress had been made on these issues, giving Iran the confidence to allow the talks to go ahead. A US official denied reports that Washington had already agreed to unfreeze Iran assets held in Qatar.
Israel has agreed to talk to Lebanon, but ruled out ceasefire negotiations with Hezbollah.
The warring parties still appeared to be far apart on key issues -- including sanctions, Lebanon and the opening of the strategic Strait of Hormuz -- and made no attempt to hide their mutual suspicion.
"Our experience in negotiating with the Americans has always been met with failure and broken promises," Ghalibaf said, shortly after landing in Pakistan.
Vance said before leaving the U.S. that if the other side was "willing to negotiate in good faith, we're certainly willing to extend the open hand".
But "if they're going to try to play us, then they're going to find the negotiating team is not that receptive", he added.
The ceasefire is already under strain, notably from Israel's continued strikes in Lebanon, which Iran and Pakistan insist is covered under the current truce.
Prime Minister Sharif, whose country's down-to-the-wire mediation got both sides to the negotiating table this week, said talks would not be easy.
"An even more difficult stage lies ahead," he said, referring to efforts to permanently end fighting that began with U.S.-Israeli strikes on Iran on Feb. 28, sparking Iranian retaliation against Israel and across the Gulf.
"This is that stage which, in English, is called the equivalent of 'make or break.'"
On the U.S. side, Trump has demanded the opening of the Strait of Hormuz as a condition for the two-week ceasefire.
The strait, through which one-fifth of the world's crude passes, has not reopened to normal traffic, however, and Trump vowed on Friday to have it open soon "with or without" Iran's cooperation.
He added that his top priority at the Islamabad talks was to ensure the Islamic republic had "no nuclear weapon. That's 99 percent of it."
Security was tight in the Pakistani capital on Saturday, with a heavy police and paramilitary presence on the streets and road diversions around the "red zone" where government and diplomatic buildings are located.
Pakistan has formulated a team of experts to facilitate the two sides in negotiations on navigation, nuclear and other key matters, a diplomatic source familiar with the matter told AFP.
The negotiations will be closely watched by other key regional players, with Egypt and Türkiye having helped with mediation, along with China, all of which Pakistan was still coordinating closely with for the talks, the source said.
In Tehran, a 30-year-old resident told AFP he was skeptical negotiations would be successful, describing most of what Trump says as "pure noise and nonsense."
