US President Donald Trump says he has delayed US military strikes on Iran after appeals from Gulf leaders who told him serious negotiations with Tehran were under way.Mr Trump said Qatari Emir Sheikh Tamim, Saudi Crown Prince Mohammed bin Salman and UAE President Sheikh Mohamed urged him to delay the attack, which he said had been scheduled for Tuesday.A senior Iranian military advisor has mocked Mr Trump for his decision, insisting the US will be "forced to retreat and surrender”.Mr Trump said the delay would allow for “serious negotiations” to take place and that his allies believed negotiations could produce an agreement acceptable to the US and countries across the Middle East."Based on my respect for the above mentioned leaders, I have instructed Secretary of War, Pete Hegseth, the Chairman of the Joint Chiefs of Staff, Gen Daniel Caine, and the United States military, that we will not be doing the scheduled attack of Iran tomorrow," he wrote on Truth Social.“This deal will include, importantly, no nuclear weapons for Iran.”But Mr Trump also warned that the US military had been ordered to remain ready for a “full, large-scale assault” if talks fail to end the war started by the US and Israel on February 28.Speaking to journalists later on Monday during a healthcare event, he said the postponement may be indefinite or last for "two or three days".▶"I put it off for a little while, hopefully maybe forever, but possibly for a little while, because we've had very big discussions with Iran and we'll see what they amount to," Mr Trump said."Also, we've informed Israel, we've informed other people in the Middle East that have been involved with us, and it's a very positive development, but we'll see whether or not it amounts to anything."Mr Trump has called on Iran's leader to admit defeat and reopen the Strait of Hormuz, the blockade of which destabilised global energy markets and caused domestic pressure on Mr Trump. Efforts to broker a ceasefire have so far stalled, as he has called Tehran's response to US proposals "unacceptable." On Sunday, he issued another warning, saying "the clock is ticking" for Iran.Iran reactionMohsen Rezaei, a military advisor to Iran's supreme leader and former commander of the Islamic Revolutionary Guard Corps, mocked Mr Trump for his decision to call off military strikes.“The US sets a deadline for a military strike and then cancels it itself, with the vain hope of making the Iranian nation and officials surrender," Mr Rezaei wrote in a post on X on Tuesday."The iron fist of the powerful armed forces and the great Iranian nation will force them to retreat and surrender.”Iranian President Masoud Pezeshkian said that “dialogue does not mean surrender” amid continuing negotiations with the US, mediated by Pakistan.He wrote on X that Tehran "will under no circumstances retreat from the lawful rights of the country and its people".Iran has sent a new 14-point proposal to end the war to Pakistan, which delivered it to the US. The text is a revised version of an earlier draft proposal that the US rejected, jeopardising a fragile ceasefire in the region.The head of Iran’s Khatam Al Anbiya Central Headquarters, the country’s main operational command, has warned the US and its allies against any new military action.Maj Gen Ali Abdollahi said Iran’s armed forces were fully prepared to respond to any attack."We announce to America and its allies: do not commit another strategic mistake or miscalculation,” he said, quoted by Press TV.“They must know that any renewed aggression or invasion by the enemies of our land and our proud nation will be met with a swift, decisive, powerful and extensive response.“We will defend the rights of the Iranian nation with all our strength and cut off the hand of any aggressor."