WASHINGTON — President Donald Trump said he is holding off a military strike on Iran planned for Tuesday at the request of the leaders of Qatar, Saudi Arabia, and the United Arab Emirates. He said the U.S. military would be prepared to launch a full, large-scale assault on Iran at a moment's notice if an acceptable deal is not reached.

Trump said the Emir of Qatar, Tamim bin Hamad Al Thani, the Crown Prince of Saudi Arabia, Mohammed bin Salman Al Saud, and the President of the United Arab Emirates, Mohamed bin Zayed Al Nahyan, had each asked him to hold off the planned attack. He suggested he would accept a 20-year suspension of Iran's nuclear programme.

"NO NUCLEAR WEAPONS FOR IRAN!" Trump wrote. He also warned: "For Iran, the Clock is Ticking, and they better get moving, FAST, or there won't be anything left of them."

The United States and its European allies claim Iran is seeking to develop nuclear weapons by enriching uranium, while Tehran has repeatedly said its nuclear programme is solely for peaceful purposes.

Iran said it had responded to the latest U.S. proposal and that exchanges with Washington were continuing through Pakistani mediators. According to Iranian media, the U.S. had failed to make any concrete concessions to Tehran.

"Iran's demands were responsible and generous," Foreign Ministry spokesperson Esmail Baghaei said. According to Tasnim news agency, Iran's demands included an immediate end to the war on all fronts, a halt to the U.S. naval blockade of Iranian ports, guarantees of no further attacks on Iran, compensation for war damage, and an emphasis on Iranian sovereignty over the Strait of Hormuz. According to Fars news agency, Washington had set five conditions in response to Tehran's proposal, including a demand that Iran keep only one nuclear site in operation and that it transfer its stockpile of highly enriched uranium to the U.S.

Israeli and U.S. forces began massive air strikes on Iran on 28 February. Tehran retaliated by firing drones and missiles at Israel and U.S. targets in countries across the Gulf. A ceasefire agreed in April has largely been observed despite occasional exchanges of fire.

Iran has continued to control the Strait of Hormuz, effectively closing the waterway through which around 20% of the world's oil and liquefied natural gas travels. The U.S. has been enforcing a blockade of Iranian ports to exert pressure on Tehran to agree to its terms.