A new agreement between Moscow and Tehran on comprehensive cooperation has been temporarily suspended due to problems that Iranian partners are facing, Russia’s RIA state news agency reported on Tuesday citing a Russian foreign ministry official.

“This is a strategic decision of the leadership of the two countries,” RIA cited Zamir Kabulov, the foreign ministry official as saying. “The process … has stopped due to problems that our Iranian partners have.”

There was no immediate comment from the Iranian side.

Russia and Iran have developed close ties in recent years, pushing against what they see as pernicious U.S. foreign policy in an effort to establish what they say would be a fairer multipolar world order.

Work on a new major agreement between Moscow and Tehran was announced in September 2022 during a meeting between Russian President Vladimir Putin and the late President of the Islamic Republic Ebrahim Raisi.

Raisi, a hardliner seen as a potential successor to Supreme Leader Ayatollah Ali Khamenei, was killed when his helicopter crashed in May.