"We have a close partnership with Tehran. And President Putin said that he was ready to use this partnership to help resolve the Iranian nuclear issue," Kremlin spokesman Dmitry Peskov told reporters.

After a call between the leaders on Wednesday, US President Donald Trump said Putin had offered to "participate" in talks on Tehran's nuclear programme, as Trump accused Iran of "slow-walking" its response to Washington's offer of a deal.

Washington and Tehran have held five rounds of talks since April to thrash out a new accord to replace the nuclear deal that Trump abandoned during his first term in 2018.

Trump said Monday that his administration would not allow "any" enrichment of uranium, despite Tehran's insistence that it has the right under the nuclear Non-Proliferation Treaty.

Iran's supreme leader Ayatollah Ali Khamenei said earlier Wednesday that Washington's proposal was against Tehran's national interest.

Russia and Iran have deepened their military ties amid Moscow's military offensive on Ukraine.

The Kremlin said earlier this week that Tehran had the "right" to a run a peaceful nuclear energy programme.