President Donald Trump appears poised to drive a stake through the heart of the Iran nuclear deal Tuesday, when he announces his verdict on US sanctions relief underpinning the landmark accord.

Officials and diplomats expect the US leader to ignore last-ditch European pleas and move to withdraw the united States from a 2015 agreement, which he insists was “very badly negotiated.”

Trump has, unsuccessfully, demanded changes to the Obama-era deal, which saw Iran mothball a suspected nuclear weapons program in eturn for massive sanctions relief.

Months of intensive talks between the United States and European allies now appear deadlocked, with Berlin, London and Paris refusing to rewrite the agreement.

The president tweeted he would announce his decision at 2pm (7pm GMT), even as British foreign secretary Boris Johnson shuttled around Washington to reach a last-gasp breakthrough.

One European diplomat echoed the mood around foreign embassies in Washington, saying “there is plainly a difference of opinion,” acknowledging Trump seems poised to walk away.

Concretely, the US president will now to decide whether to continue to waive sanctions on Iran’s central bank and its oil sector dealings, a key pillar of the agreement.

“It’s pretty obvious to me that unless something changes in the next few days, I believe the president will not waive the sanctions,” the European official said.

“I would like to pretend to you today that I feel that there is a chance of the existing (deal) remaining intact,” the official said. “I think that that chance may exist but it is very small.”

A French official said President Emmanuel Macron left the United States last week after a similar diplomatic offensive “convinced that we would get a negative decision.”

“We are preparing more for the scenario of a partial or total withdrawal than for the US staying in the deal,” the official adde