Washington, Oct 6 (IANS): US President Donald Trump is expected to "decertify" the 2015 international nuclear deal with Iran and turn it back to Congress for possible renewed sanctions, senior US officials said.

Trump is likely to announce his plans in a speech next week in which he will say the agreement was not in US national interest, the officials said.

The move would mark the first step in a process that could eventually result in the resumption of US sanctions against Iran, potentially derailing a deal limiting Iran's nuclear activities reached in 2015 with the US and Britain, China, France, Germany and Russia, the New York Times reported.

Lawmakers would have 60 days to decide whether to reimpose sanctions that were suspended under the agreement. A decertification could also open the door to renegotiate the deal, although Iranian President Hassan Rouhani has said that was not an option.

Trump, who called the pact an "embarrassment" and "the worst deal ever negotiated", faces an October 15 deadline for certifying that Iran was complying with its terms.

Meeting with his top military aides at the White House on Thursday, Trump said Iran didn't live up to "the spirit of the agreement".

"The Iranian regime supports terrorism and exports violence, bloodshed and chaos across the Middle East. That is why we must put an end to Iran's continued aggression and nuclear ambitions," he said.

White House spokeswoman Sarah Huckabee Sanders did not say what the President planned to do, other than saying he would "make an announcement about the decision that he's made on a comprehensive strategy that his team supports" in the coming days.

Democrats argued that Trump should certify the agreement, warning that the administration's ability to press Iran on other activities it objects to would be compromised - rather than enhanced - if the US threw the future of the agreement into question.

The deal is also contentious inside the administration.

Secretary of State Rex Tillerson and Defence Secretary Jim Mattis both urged Trump not to back out of it because that would free Iran to begin producing uranium and reprocessing plutonium immediately, not after 13 years, as is stipulated in the agreement.