US President Donald Trump said he would "hold off" an attack on Iran scheduled for today at the request of Gulf leaders.Trump said on his Truth Social network yesterday that "serious negotiations" were now underway with Iran and that Gulf states believed "a deal will be made."But he said Washington was ready for a "full, large scale assault of Iran, on a moment's notice, in the event that an acceptable Deal is not reached."On his Truth Social platform, Trump said he was asked by His Highness the Amir Sheikh Tamim bin Hamad al-Thani, Saudi Crown Prince Mohammed bin Salman and UAE President Mohamed bin Zayed al-Nahyan “to hold off on our planned military attack” on Iran, “which was scheduled for tomorrow”.His comments came after Iran said it submitted a response to the latest US proposal via mediator Pakistan.Iran sent the proposal to the US with terms that appeared similar to offers Washington has previously rejected, although a senior Iranian official told Reuters yesterday that the US had softened positions on some issues.A Pakistani source confirmed that Islamabad, which has conveyed messages between the sides in the war in the Middle East since hosting the only round of peace talks last month, had shared the latest proposal with Washington. But the source suggested progress had been difficult.The sides "keep changing their goalposts," the Pakistani source said, adding: "We don't have much time."Iranian Foreign Ministry spokesperson Esmaeil Baghaei confirmed that Tehran's views had been "conveyed to the American side through Pakistan" but gave no details. Washington did not immediately comment.The Iranian proposal, as described by the senior Iranian source, appeared similar in many respects to Iran's previous offer, which US President Donald Trump rejected last week as "garbage".It would focus first on securing an end to the war, reopening the Strait of Hormuz — a major oil supply route that Iran has effectively blockaded — and lifting maritime sanctions.Contentious issues around Iran's nuclear programme and uranium enrichment would be deferred to later rounds of talks, the source said.However, in an apparent softening of Washington's stance, the senior Iranian source said the United States had agreed to release a quarter of Iran's frozen funds — totalling tens of billions of dollars — held in foreign banks. Iran wants all the assets released.The Iranian source also said Washington had shown more flexibility in agreeing to let Iran continue some peaceful nuclear activity under supervision of the International Atomic Energy Agency.Iran's Tasnim news agency separately quoted an unidentified source as saying the US had agreed to waive oil sanctions on Iran while negotiations were under way.Iranian officials did not immediately comment on Tasnim's report, which a US official, who declined to be named, said was false.A fragile ceasefire is in place after six weeks of war that followed US-Israeli airstrikes on Iran. But talks mediated by Pakistan have stalled and Trump has said the ceasefire is "on life support".Washington has previously demanded Tehran dismantle its nuclear programme and reopen the Strait of Hormuz, which normally carries one-fifth of the world's seaborne oil and liquefied natural gas supply.Iran has been demanding compensation for war damage, an end to a US blockade of Iranian ports and a halt to fighting on all fronts, including in Lebanon.Trump is expected to meet top national security advisers today to discuss options for resuming military action, Axios reported.Baghaei said Tehran was prepared for all scenarios."As for their threats, rest assured that we are fully aware of how to respond appropriately to even the smallest mistake from the opposing side," he told a televised weekly press conference.