Russian Prime Minister Dmitri Medvedev said in an interview released Sunday that Syrian President Bashar al-Assad's had committed a possibly "fatal" mistake by not implementing democratic reforms in his country, dpa reported.
"He should have acted much more quickly and reached out to the peaceful opposition which was ready to sit at the negotiating table with him," the Russian News Agency Novosti quoted Medvedev as telling CNN.
"This was his grave mistake, and possibly a fatal one," he said on the sidelines of the Davos World Economic Forum in Switzerland.
He warned that prospect of al-Assad remaining in power was "getting smaller and smaller" by the day, but that only the Syrian people can decide his fate.
"I repeat again, this must be decided by the Syrian people. Not Russia, not the United States, not any other country," Medvedev said.
Syria has been locked in a 22-month conflict which has so far claimed the lives of 60,000 people, according to UN estimates.
Russia has blocked UN sanctions against Syria, its main ally in the region, and has continued to supply the al-Assad regime with weapons.
World powers remain divided on how to solve the crisis. The US and many Arab and European countries have called on al-Assad to step down, while Russia, China and Iran have rejected such a proposal.
"The task for the international community now is to sit with the parties down for negotiations, and not just demand that al-Assad go," the Russian premier said.
Medvedev's statement came as Syria reiterated that it would drop legal proceedings against any opposition figures who return to the country to participate in a "national dialogue" called for by al-Assad during a recent speech.
Syria's Higher Judicial Council announced the decision in a statement carried by the state news agency. The report gave no further details.
On the ground, Syrian rebels clashed with government forces loyal to al-Assad in southwest Damascus, forcing the closure of the main highway linking Damascus to the southern town of Daraa, activists said.
The Syrian army has been for weeks mounting ground and air assaults to drive insurgents from areas on outskirts of Damascus.
The fighting came as United Nations humanitarian chief Valerie Amos arrived in Damascus and visited a number of refugee spots near the capital. Her visit came ahead of a scheduled UN aid conference due to held in Kuwait on January 30.
The conference aims to raise 1.5 billion dollars for the millions of Syrian refugees stranded in and outside Syria. The UN has recently said that about 4 million Syrians are in urgent need of humanitarian assistance, and that at least 2 million of them were internally displaced.