UN-Arab League envoy Lakhdar Brahimi Thursday called for setting up a transition government in Syria until elections can be held, ahead of his visit to Moscow at the weekend.
"We need to form a government with all powers ... which assumes power during a period of transition," Brahimi said in Damascus. "That transition period will end with elections."
The opposition has repeatedly demanded that President Bashar al-Assad should step down before any political solution can be reached.
Brahimi arrived in Syria on Sunday in a fresh bid to end the 22-month conflict, which the opposition says has claimed more than 45,000 lives.
But the veteran Algerian diplomat has failed to make any progress towards brokering a deal since starting his mission in August.
Brahimi is to meet Russian Foreign Minister Sergei Lavrov in Moscow on Saturday, said Russian Foreign Ministry spokesman Alexander Lukashevich.
"We plan to discuss the whole range of issues concerning political and diplomatic settlement in Syria, including Brahimi's recent efforts that are targeted at stopping violence and the launch of a comprehensive national dialogue between the authorities and the opposition in compliance with the Geneva agreements," said Lukashevich, according to Itar Tass news agency.
He was referring to agreements reached in Geneva in June at the Action Group for Syria meeting.
Lukashevich said Syrian Deputy Foreign Minister Faisal al-Mokdad had met with Lavrov in Moscow, but did not give details.
He denied speculation about any Russian-US plan for ending the conflict. "There is no such plan," Lukashevich said. "By meeting with Lakhdar Brahimi and our American colleagues, we are trying to find measures to overcome the crisis on the basis of the Geneva communiqué."
Russia, a traditional ally and arms supplier of Syria, has repeatedly vetoed United Nations resolutions against al-Assad.
Calling for "a legally elected president" to step down was not a part of the Geneva agreements, Lukashevich said.
He quoted Lavrov as saying: "If a task is set to take the president's head, this will lead to the bloodshed. Those who seek to achieve such goals should bear responsibility for their actions."