France's Macron 'considers' Iran trip after Rouhani invite

French President Emmanuel Macron is considering a visit to Iran after speaking to his Iranian counterpart as US President Donald Trump said he was "decertifying" the landmark nuclear deal with Tehran.

Macron told Iranian President Hassan Rouhani on Friday that France remained committed to the 2015 nuclear agreement which, besides the United States, was also negotiated with Britain, China, Russia and Germany. 

The 2015 Joint Comprehensive Plan of Action, as the deal is formally titled, was crafted over 21 months of hair-pulling negotiations.

Trump unveiled an aggressive new strategy towards Iran on Friday during a speech at the White House, announcing he would not re-certify the landmark 2015 nuclear accord.

"A trip to Iran by the president, at the invitation of President Rouhani, has been considered," the Elysee said, while the Iranian presidential website said the visit would happen next year.

Macron said the US decision "will not put an end to the Iranian nuclear accord and that together all the parties in France and its European partners will continue to meet their commitments."

Rouhani assured Macron that Iran in turn "will continue to carry out its commitments" in the nuclear accord, the Elysee said.

The French leader added that it was necessary to have a dialogue with Iran on other strategic issues including Tehran's ballistic missile programme and stability in the region.

Macron also spoke to Rouhani of his "wish to work with Iran for a lasting political solution to the Syrian crisis." Tehran is a staunch supporter of President Bashar al-Assad's regime. 

Macron's visit to Iran would be the first by a French head of state or government since 1976. French Foreign Minister Jean-Yves Le Drian is set to travel to the Islamic Republic in the next few weeks.

Earlier on Friday the leaders of France, Germany and Britain issued a joint statement saying they were "concerned" about Trump's decision while reiterating their commitment to the deal.

During a blistering attack on Iran, Trump announced tough new sanctions on the Islamic Revolutionary Guard Corps (IRGC), vowing to target officials, agents and affiliates of the group.

Trump, who has been railing against the Iran deal since before he was elected in November last year, called the nuclear deal "one of the worst" in US history, and warned America could leave it "at any time".