Russia does not see keeping Bashar Assad in power as a matter of principle, the Foreign Ministry in Moscow said on Tuesday in comments that suggested a divergence of opinion with Iran, the Syrian president's other main international backer.

Fueling speculation of Russian-Iranian differences over Assad, the head of Iran's Revolutionary Guard Corps suggested on Monday that Tehran may be more committed to him than Moscow is.

However, one senior regional official cautioned against reading too much into the public statements on Assad, saying there is no difference between Russia and Iran over him. They agree on his staying in office, and that it is up to the Syrian people to elect their president, the official said.