French President Emmanuel Macron inside the Pantheon monument during a ceremony in Paris, Friday, April 27, 2018 . Macron is paying homage to victims of the slave trade and celebrating 170 years since France abolished slavery in its colonies. (AP Photo/Thibault Camus, Pool)

French President Emmanuel Macron and Iran's Hassan Rouhani agreed on Wednesday during a phone call to work toward "the continued implementation of the nuclear deal" despite the US decision to withdraw from the agreement, the French presidency said.

"The French and Iranian presidents agreed to pursue their joint efforts with all nations involved, with the aim of continued implementation of the nuclear deal and maintaining regional stability," Macron's office said in a statement.

US President Donald Trump announced Tuesday that he was pulling out of the landmark 2015 nuclear accord, calling it "defective at its core".

It was a stark diplomatic defeat for France, Germany and Britain, which had lobbied hard for Trump to stand by a deal whose terms they say Tehran has largely respected.

But during their call, Macron told Rouhani that France would also seek an expanded accord in a "mutually beneficial framework" covering Iran's ballistic missile development, its involvement in several crises roiling the Middle East, and the prospects for its nuclear programme once the 2015 accord expires in 2025.

Macron's office said France and Iran's foreign ministers would meet "without delay" for talks.

Rouhani had previously warned that Iran could resume uranium enrichment "without limit", though he said he would discuss Iran's response with other parties to the deal before announcing a decision.

Iran has always denied seeking a nuclear weapon, insisting its atomic programme was for civilian purposes.