Russia will not attend a Friends of Syria meeting in Paris on Friday which seeks to co-ordinate Western and Arab efforts to stop the violence in the country, foreign minister Laurent Fabius said.
"Russia was invited. They made it known that they did not want to participate, which is not a surprise," he told reporters.
Russia, a traditional ally of Syria, and China did not attend previous meetings of the group.
The Paris meeting will be the third such gathering after one in Tunis in February and another in April in Istanbul called for tougher action against the Assad regime.
The United States, France, Britain, Germany, and Arab nations Saudi Arabia and Qatar are leading members of the Friends, whose more than 60 members include most of the EU states and many countries making up the Arab League.
Russia has been under sustained pressure from the West to publicly call for Syrian President Bashar al-Assad to quit amid a spiralling conflict that has claimed 15,000 lives, but Moscow has rejected imposing any outside solution.
Moscow on Tuesday accused the West of seeking to "distort" an agreement reached last weekend in Geneva on a plan for a political transition to end the conflict.
Foreign minister Sergei Lavrov hailed the accord based on proposals by envoy Kofi Annan as an "important step" but said that Western capitals had already read more into the final statement than what was written on paper.
His comments came just after Annan's spokesman told reporters that a "shift" in positions by Russia and its diplomatic ally China at the Geneva talks should not be underestimated.