Russian Foreign Minister Sergei Lavrov said Wednesday that Syrian opposition representatives would risk losing influence in peace efforts if they do not attend planned talks in Moscow.
The refusal of prominent opposition figures to attend the Jan. 26-29 meeting, intended to bring together representatives of President Bashar Assad and some Syrian opposition groups, has dealt a blow to Russian efforts to find a solution to the Syrian conflict.
"Those who decide not to take part in this event, they will lose in terms of their positions in the peace talks process as a whole," Lavrov told a news conference.
Moscow, one of Assad's top allies, says it still hopes the Western-backed National Coalition for Syrian Revolutionary and Opposition Forces will be represented at the talks.
Some 200,000 people have been killed in the conflict in Syria, which started with street protests against Assad in March, 2011, and then descended into a civil war in which radical Islamist groups have gained the upper hand.
In rejecting the invitation to Moscow, the Western-backed opposition Syrian National Coalition said on Jan.7 it would sit down to talks only if they would lead to Assad giving up power.
Moscow says the emphasis should be on fighting Islamist militants and that Assad's exit should not be a precondition to peace talks.