Russia disputes US claim on Syria chemical weapons

Moscow: President Vladimir Putin's foreign affairs adviser says Moscow is not convinced with Washington's claim that Syrian regime had used chemical weapons against the opposition.

Yuri Ushakov told reporters Friday that the information provided by US officials to Russia "didn't look convincing."

The White House said Thursday that the US has conclusive evidence that Syrian President Bashar Assad's regime has used chemical weapons against opposition forces, crossing what President Barack Obama has called a "red line" that would trigger greater American involvement in the crisis. Obama's deputy national security adviser Ben Rhodes said Obama was planning to step up military assistance to Syrian rebels.

Ushakov warned that providing such assistance could derail efforts to convene a Syria peace conference.