The three European signatories to the 2015 nuclear deal with Iran said they were "united in underlining the dangerous nature of this decision".

"It will significantly constrain the IAEA (International Atomic Energy Agency's) access to sites and to safeguards-relevant information," they added.

The statement from the European nations follows criticism from Washington on Monday of Tehran's decision to restrict IAEA access to sites.

"We urge Iran to stop and reverse all measures that reduce transparency and to ensure full and timely cooperation with the IAEA," the UK, France and Germany said.

They added it was their objective to preserve the 2015 deal, known as the Joint Comprehensive Plan of Action (JCPOA), which lifted economic sanctions on Iran in exchange for agreements on limits to its nuclear programme.

The European signatories, which stuck with the deal after the US withdrew under former president Donald Trump in 2018, said they would "support ongoing diplomatic efforts for a negotiated solution allowing for the return of Iran and the US to full compliance".

Biden has signalled readiness to revive the nuclear deal but insists Iran first returns to all its nuclear commitments.

The Biden administration has said it is willing to join EU-led talks with Iran in search of a compromise.

Iran said it was limiting inspections because Trump-era sanctions had not been lifted following Sunday talks in Tehran with IAEA director Rafael Grossi meant to lay the foundations for political discussion.

"We take note of the conclusion of a temporary bilateral understanding between the IAEA and Iran which preserves for up to three months the possibility of access to certain information," the UK, France and Britain said referring to Grossi's visit to Tehran.

The changes to the IAEA's monitoring and inspection regime, ordered by Iran's conservative-dominated parliament last year, are the latest in a series of retaliatory measures Iran has adopted in response to Trump's 2018 withdrawal from the agreement.