Iranian President Hassan Rouhani on Tuesday warned his US counterpart Donald Trump that abandoning a nuclear deal that the Tehran government signed with world powers in 2015 would lead to "serious consequences".
Speaking live on television, Rouhani said his government had kept its end of the deal and warned Trump not to tear up the agreement, which had also been signed by Russia, China, Germany, the UK and France.
"I am telling those in the White House that if they do not live up to their commitments, the Iranian government will react firmly," Rouhani said.
"If anyone betrays the deal, they should know that they would face severe consequences," he added.
Trump has said that unless the US' European allies put right what he has described as "terrible flaws" in the deal by May 12, his government would re-establish economic sanctions on Iran, dealing the pact a major blow, Xinhua news agency reported.
Rouhani stressed that Iran was complying with the deal, as has been confirmed a dozen times by the International Atomic Energy Agency, whose Director General Yukiya Amano said in March that a possible failure of the agreement would be a great loss.
French President Emmanuel Macron was in Washington in an attempt to try and persuade Trump not to walk away from the accord.
Russian Foreign Minister Sergei Lavrov said on Monday he had agreed with his Chinese counterpart that Moscow and Beijing would try to block any US attempt to wreck the nuclear deal.
Iran has said it would ramp up its nuclear programme if the deal collapses.