The United States and Iran remain locked in a standoff with no clear off-ramp with an expert warning President Donald Trump is struggling to shift momentum.

The Strait of Hormuz remains closed, with the ceasefire set to expire in less than 48 hours and no signs of meaningful progress in peace negotiations.

WATCH THE VIDEO ABOVE: US-Iran standoff reaches critical point as ceasefire expires

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A second round of talks is expected soon, despite Iranian officials criticising Washington’s refusal to abandon its hardline demands.

Military strategy expert Professor Robert Pape told Sunrise on Monday the conflict had become a “zero-sum” escalation with no clear exit.

“What you are observing now is not just an air campaign that started out as a few days and is extending. This has become an escalation trap,” he said.

“There were some initial rounds, some initial ideas of some quick victory that failed. They actually tactically succeeded, but failed to achieve the victory. And then President Trump has been going up the escalation trap, rung by rung, looking for that strategic victory.”

Pape said Iran’s ability to shut down the Strait of Hormuz with minimal resources had shifted the balance of power, giving it outsized global leverage.

Military strategy expert Professor Robert Pape has told Sunrise the conflict had become a ‘zero-sum’ escalation with no clear exit.  Credit: Sunrise

He warned neither side had a clear incentive to step back, despite obvious global consequences.

“The United States doesn’t want to back down and have to accept a giant loss, a defeat, which could really end President Trump’s presidency, at least politically, for all intents and purposes,” he said.

“Iran doesn’t want to give up that world power, at least its emerging world power, because it’s just so extraordinary and gives it so many benefits.

“That’s the zero-sum nature of the escalation trap, and neither side really has good reasons right now to give up. The big reason to pull back is because it’s hurting the world.

“Those two actors are accepting world pain because they don’t want to face the political losses that surrender involves.”

Pape said the seven-week conflict had already cost the United States a significant amount in its “image of power”, with even a far weaker nation able to withstand and challenge its influence.

“Before this point, we were able to project this idea that we were this awesome 800-pound gorilla, we could basically beat up almost anybody on the planet, and we kind of papered over what happened with the forever wars,” he said.

“America has lost a tremendous amount of prestige and actual visible power, and you see it with the Europeans. They won’t obey President Trump. You see it with the Japanese; they won’t come. Australia is not looking to get in on this.

“President Trump can ask for the world’s help, he doesn’t have the power to budge a single country.”

Pape warned that without a breakthrough, the conflict was likely to continue dragging on, with both sides unwilling to absorb the political cost of backing down.