WASHINGTON — US President Donald Trump said Monday that a "total termination" of the Iran nuclear deal remains possible, after refusing to certify the 2015 accord and leaving its fate to Congress.

His comments came as the EU announced it was sending its chief diplomat to Washington next month to try to save the agreement that saw Tehran dramatically scale back its nuclear ambitions in return for an end to punishing sanctions.

Speaking to reporters ahead of a Cabinet meeting, he said: "I feel strongly about what I did. I'm tired of being taken advantage of. It might be total termination, that's a real possibility, some would say that's a greater possibility."

But he also appeared to leave the door open for a new deal, while praising the negotiation skills of his Iranian counterparts. "It also could turn out to be very positive. We'll see what happens," he said. "I thought the tone of the Iranian leaders was very modified and I was happy to see that but I don't know if that means anything.

"They're great negotiators, they negotiated a phenomenal deal for themselves, but a horrible deal for the United States."

Trump alarmed allies across the Atlantic with a belligerent speech on Friday in which he stopped short of pulling out of the agreement but warned he could do so at any time, restating his belief the deal was letting Iran off the hook.

EU ministers have warned that ditching the deal when Iran has repeatedly been certified as keeping up its end of the bargain would send a signal to North Korea that negotiating with the international community is a waste of time.

Federica Mogherini, the EU's foreign policy head, said Monday she would "be in Washington in early November" to urge US lawmakers not to pull out of the deal, known as the JCPOA, which was negotiated with Iran by the US, Britain, France, China, Germany and Russia.

There is broad support among US lawmakers for fresh pressure on Iran over its continued missile development and subversive activities in the region — factors that Trump says violate the "spirit" of the agreement.

Western diplomats say European powers share some of these concerns but believe they should be dealt with in other forums and warn it would be a mistake to sacrifice the nuclear deal. Tehran has warned such action would mean Washington had broken its end of the bargain, and thus likely signal the end of their own compliance.

Trump's Iran statement on came four months after he moved to pull out of the 196-nation Paris agreement on climate change, signaling a widening gulf between Washington and its closest European allies. — AFP