The US and Iran failed to reach an agreement to end their war despite marathon talks that concluded on Sunday in the Pakistani capital Islamabad, jeopardising a fragile ceasefire.
Each side blamed the other for the failure of the 21-hour negotiations to end fighting that has roiled the global economy and sent oil prices soaring since it began more than six weeks ago.
"The bad news is that we have not reached an agreement, and I think that's bad news for Iran much more than it's bad news for the United States of America," said Vice President JD Vance, the head of the US delegation.
"So we go back to the United States having not come to an agreement. We've made very clear what our red lines are."
Iran's Parliamentary Speaker Mohammad Baqer Qalibaf, who led the authoritarian regime's delegation along with Foreign Minister Abbas Araqchi, blamed the US for not winning Iran's trust despite his team offering "forward-looking initiatives".
"The US has understood Iran's logic and principles and it's time for them to decide whether they can earn our trust or not," Qalibaf said on social media.
Both the US and Iranian delegations have now left Islamabad to return home, Pakistani sources told Reuters.
The talks, after a ceasefire earlier in the week, were the first direct US-Iranian meeting in more than a decade and the highest-level discussions since the 1979 Islamic Revolution.
Vance said Iran had chosen not to accept American terms, including not to build nuclear weapons.
"We need to see an affirmative commitment that they will not seek a nuclear weapon and they will not seek the tools that would enable them to quickly achieve a nuclear weapon," he said.
"That is the core goal of the president of the United States, and that's what we've tried to achieve through these negotiations."
Iran's semi-official Tasnim propaganda network said "excessive" US demands had hindered reaching an agreement. Other Iranian media said there was agreement on a number of issues but that the Strait of Hormuz and Iran's nuclear programme were the main points of difference.
Pakistan's Foreign Minister Ishaq Dar said it was "imperative" to preserve the two-week ceasefire that was agreed last Tuesday as the sides attempt to wind down a war that began on February 28 with air strikes by the US and Israel on Iran.
Israeli security cabinet minister Zeev Elkin told Army Radio that more talks were still an option, but added: "The Iranians are playing with fire."
In his brief press conference, Vance did not mention reopening the Strait of Hormuz, a choke point for about 20 per cent of global energy supplies that Iran has blocked since the war began.
Vance said he had spoken with President Donald Trump as many as a dozen times during the talks. But even as the negotiations continued, Trump said on Saturday that a deal was not entirely necessary.
"We're negotiating. Whether we make a deal or not makes no difference to me, because we've won," he told reporters.
Even as the talks were taking place, US ally Israel continued bombing Tehran-backed Hezbollah terrorists in Lebanon, insisting that that conflict was not part of the Iran-US ceasefire. Iran says the fighting in Lebanon must stop.
The Israeli military said it struck Hezbollah rocket launchers overnight into Sunday and black smoke could be seen rising in the southern suburbs of the Lebanese capital Beirut on Sunday. In Israeli villages near the border, air raid sirens sounded, warning of incoming rocket fire from Lebanon.
Tehran is demanding control of the Strait of Hormuz, payment of war reparations and a ceasefire across the region, including in Lebanon, according to Iranian state TV and officials, as well as the release of its frozen assets abroad. It has been curiously quiet about reparations for Iranian attacks on many of its neighbours in the region.
Tehran also wants to collect transit fees in the Strait of Hormuz.
Despite the differences in Islamabad, three VLCCs fully laden with oil passed through the Strait of Hormuz on Saturday, shipping data showed, in what appeared to be the first vessels to exit the gulf since the ceasefire deal.
Hundreds of tankers are still stuck in the gulf, waiting to exit during the two-week ceasefire period.
Trump wants free passage for global shipping through the strait and the crippling of Iran's nuclear enrichment programme to ensure it cannot produce an atomic bomb.
Tehran has long denied seeking to build a nuclear weapon.
(Reporting by Reuters bureaus worldwide; Writing by Idrees Ali, Lisa Shumaker, Raju Gopalakrishnan and Matthias Williams; Editing by William Mallard and Gareth Jones)
