A major threat facing Russia in Syria is the possible return of Islamic State (ISIS) militants currently fighting there to Russia, Russian Foreign Minister Sergei Lavrov has said, adding that Moscow will work to prevent such a situation, and it should succeed in these efforts.

"As for the risks for the Russian Federation, the [Russian] president has said about these risks very clearly: the main risk being posed by this entire situation is that the militants whose number amounts to thousands and who are natives of [former] Soviet countries, including Russia, will return and will do their black deeds in our country," Lavrov told a press briefing on Thursday.

"We strongly want to prevent these risks. I am confident that we will succeed," he noted.