A leading Syrian opposition group is calling on the United Nations to retake charge of the peace process for war-torn Syria, after Russia announced it would host parallel talks later this month.

The Higher Negotiation Committee says Russia is undermining the U.N. and imposing its own rules for Syria, where over 400,000 people have been killed in a six-year-long civil war.

Russia is a steadfast ally of Syrian President Bashar Assad and Russian forces are fighting alongside Syrian government troops against armed rebels and other opponents. Moscow says it's fighting a war on terrorism.

The HNC statement on Thursday didn't say whether the opposition would attend the November 18 talks due in Sochi — 10 days before the U.N. convenes its own talks between the government and opposition in Geneva.