WASHINGTON -- US President Donald Trump said Monday that he has instructed the Pentagon not to launch military strikes on Iran Tuesday as US allies in the Gulf are working to help reach an acceptable peace deal.

"We will NOT be doing the scheduled attack of Iran tomorrow," Trump wrote on Truth Social.

The president added that he has further instructed the Pentagon "to be prepared to go forward with a full, large scale assault of Iran, on a moment's notice, in the event that an acceptable Deal is not reached."

Trump said "serious negotiations" are taking place and that, in the opinion of Gulf leaders, a deal will be made, which will be "very acceptable" to the United States, all countries in the Middle East, and beyond.

"This Deal will include, importantly, NO NUCLEAR WEAPONS FOR IRAN!" he wrote.

Trump said he held off on the planned attacks at the request of leaders from Qatar, Saudi Arabia and the United Arab Emirates.