IF Iran does not sit down with US diplomats to discuss scrapping its nuclear ambitions on Saturday, massive bombing raids – and the prospect of an extended and costly US/Iran conflict could result, a national security expert warned today. Historically Tehran has refused to meet US negotiators as a matter of political principle but Donald Trump is demanding face-to-face meetings with top political and military brass from both nations.

He has already announced the two countries will meet in Oman on Saturday – but Iran almost immediately contradicted the president insisting the talks would be conducted through an intermediary. Speaking from the White House’ Oval Office last night Trump warned Iran “would be in great danger” if the projected talks were stymied. He said: “We’re having direct talks with Iran, and they’ve started. It’ll go on Saturday.

“We have a very big meeting, and we’ll see what can happen. And I think everybody agrees that doing a deal would be preferable.

“Iran cannot have a nuclear weapon, and if the talks aren’t successful, I actually think it will be a very bad day for Iran”.

In recent days the US has been bolstering military assets in the Middle East. One carrier strike group is already operating in the region and a second is en route from Asia.

B-2 Spirit stealth bombers, which can be armed with nuclear weapons, have also been sent to the Indian Ocean base of Diego Garcia, comfortably in range of Iran.

Dr Oz Hassan, Reader of National Security in the Department of Politics and International Studies, at The University of Warwick, told express.co.uk Trump was more than capable of starting a war with Iran – but that it could bog America down in the region for a long time.

He said: “Donald Trump’s threats to bomb Iran should not be dismissed as empty words.

“While Trump often uses tough language to pressure rivals, his actions suggest he is prepared to follow through—making the risk of military escalation very real if tensions rise again.

“If the United States were to bomb Iran, what it looked like would depend on the goal. A small, targeted strike—perhaps on a nuclear site—might send a message but wouldn’t do much to stop Iran’s nuclear programme.

“A serious attempt to destroy Iran’s capabilities would require a large, complex military operation, involving stealth bombers, powerful bunker-busting bombs, and attacks on Iran’s air defences and military systems. This would look less like a quick raid and more like the start of a major war.”

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