"The Islamic Republic of Iran favours talks and negotiations and, if the US really wants to talk, before anything else it should lift all sanctions," Rouhani said in remarks aired live on state television.

Rouhani, speaking at the foreign ministry after meeting with his top diplomat, Mohammad Javad Zarif, said Iran was ready for talks regardless of whether or not the US was party to a landmark nuclear deal.

"Whether they want to come into the JCPOA or not, it's up to them," said Rouhani, referring to the 2015 nuclear deal known formally as the Joint Comprehensive Plan of Action.

The Iranian foreign minister on Monday confirmed reports that he had turned down an offer from a US senator to meet President Donald Trump at the White House.

Tensions between Iran and its arch-foe the United States have soared since Trump announced last year that the US was withdrawing from the deal and began reimposing sanctions against the Islamic republic.

The nuclear deal set limits on Iran's nuclear programme in exchange for the removal of punitive economic sanctions.