Russian President Vladimir Putin will host his Iranian counterpart Ebrahim Raisi in Moscow on Wednesday, the Kremlin said, amid talks aimed at reviving the Iran nuclear deal.
The meeting will be Raisi's most important official visit abroad since he took office in August, and the first visit by an Iranian president to Russia since 2017.
The leaders will discuss the "whole range of issues of bilateral cooperation", including the 2015 deal that offered Tehran sanctions relief in exchange for curbs on its nuclear programme, the Kremlin said in a statement.
In 2018, Washington announced its unilateral withdrawal from the agreement under former president Donald Trump, prompting Iran to walk back on its commitments.
Since last year, Iran has been in talks with the signatories of the accord -- the United States, France, Britain, Russia, China and Germany -- to restore the deal, but negotiations stopped in June after Raisi's election.
They resumed in November.
Russia's foreign minister Sergei Lavrov earlier this month noted "real progress" in the talks.
Moscow and Tehran have strong political, economic and military ties, shared interests in Afghanistan, and are key allies of Syrian President Bashar al-Assad in his country's decade-long civil war.