US President Donald Trump on Saturday said he has cancelled planned military strikes on Iran, provided Tehran rapidly reaches an agreement with Washington, after reports suggested the United States was preparing fresh attacks on Iranian targets.

In a post on Truth Social, Trump said the decision was taken in coordination with Israel.

"I have agreed, for the future benefit of the WORLD and, likewise, the survival of a successful and prosperous Iran, to cancel the attack, subject to being able to rapidly make a DEAL."

Trump said he made the decision after being "asked" by Iran and several countries in the Middle East to delay military action to allow time for negotiations.

He added that any agreement would require the "Immediate, Complete, and Total OPENING OF THE HORMUZ STRAIT, and an end to Iran's nuclear threat."

The announcement came amid reports by US media that Washington had been considering a fresh wave of strikes on Iran's energy and strategic infrastructure over the weekend.

Earlier, Tehran accused the United States of escalating tensions in the region and warned that any country co-operating with Washington would be "engulfed by the flames of war."

Separately, the US government issued a security alert advising Americans across the Middle East to remain vigilant and be prepared for possible travel disruptions in the event of further escalation.

"Americans currently in the Middle East should exercise caution and heightened vigilance and should be prepared for flight cancellations, periodic airspace closures, and potential travel disruptions," the advisory said.