Moscow will not tell Bashar Al-Assad to stand down, Russian Foreign Minister Sergei Lavrov said, stressing that while the Syrian president was not an ally it was not up to other nations to interfere.
After 10 months of internal conflict in Syria that the United Nations says has killed more than 5,400 people, Russia is under growing pressure to take a firmer line on Assad and his regime.
Russia, a veto-wielding UN Security Council member, has exasperated the West by insisting it will not back a resolution calling on Assad to go.
"I don't think Russian policy is about asking people to step down. Regime change is not our profession. Some other countries...," Lavrov said in Australia on Tuesday.
"It is up to the Syrians themselves to decide how to run the country, how to introduce the reforms, what kind reforms, without any outside interference," he told the national broadcaster ABC.
"We're not a friend, we're not an ally of president Assad. We never said that president Assad remaining in power is the solution to the crisis."
A draft UN resolution on Syria seen by AFP calls for the regime to put an immediate stop to violence against protesters and for Assad to hand power to his deputy.
Meanwhile, Syria's opposition urged the international community to act and deplored its failure to stop "massacres" amid spiralling violence ahead of a UN Security Council showdown on Tuesday.
UN Secretary General Ban Ki-moon, in neighbouring Jordan for talks on Middle East peace, urged the Security Council to overcome bitter differences over Syria to increase pressure to end the bloodshed.
US Secretary of State Hillary Clinton is leading a Western charge to press Russia to back Security Council action to stop a crackdown on dissent the United Nations says has killed more than 5,400 people in the past 10 months.
Veto-wielding Russia has objected to a resolution introduced by Morocco which calls for the regime to put an immediate stop to violence against protesters and for-Assad to hand power to his deputy.
The text seen by AFP also calls for the formation of a unity government leading to "transparent and free elections," while stressing there will be no foreign military intervention in Syria.
Assad's government has already flatly rejected a similarly worded resolution proposed by the Arab League.
Russia's deputy foreign minister, Gennady Gatilov, said on Tuesday that pushing the resolution through would be the "path towards civil war" in a country where an increasingly bold insurgency is harrowing regime forces.
The opposition Syrian National Council deplored the global community's lack of "swift action" to protect civilians "by all necessary means," in a statement on Facebook.
On Monday, "the regime waged a bloody campaign of massacres and terrorism that killed 100 Syrians including women and children... in Homs, using tanks and heavy weapons," it said.
The SNC, the most representative group opposed to Assad, reaffirmed the "people's determination to fight for their freedom and dignity," stressing they "will not give up their revolution, whatever the sacrifices."
"The regime is taking advantage of the cover provided to it by some regional and international parties to escalate its crackdown," it added, in an apparent allusion to Iran and Russia, after calling for a "day of mourning and anger."
The head of the now defunct Arab League observer mission to Syria, General Mohammed Ahmed Mustafa al-Dabi, said there had been a marked upsurge in violence since last Tuesday. Nearly 400 people have been killed since.
On Monday alone, almost 100 people, including 55 civilians, were killed during a regime assault on the city of Homs, said the Syrian Observatory for Human Rights.
The unrest, which also saw 25 soldiers killed, marked one of the bloodiest days of a revolt that erupted in March, inspired by a wave of Arab uprisings that last year overthrew authoritarian leaders in Egypt, Libya and Tunisia.
On Tuesday, at least eight civilians were killed in separate incidents in Homs and in Idlib province in the northwest, the Observatory said.
Demonstrations were held in southern Daraa province as thousands attended the funeral of a slain protester, activists said.
Regime forces began blowing up houses in the protest hub of Rankus, north of Damascus, said an activist, who urged the world to help civilians besieged in the town for a week.
"The main road to Rankus is completely cut off, as well as communications, water and electricity, and there is no milk for babies. Help them. Send them food. They are dying," said Abu Omar, an activist spokesman for the town.
Amid the escalating violence, which prompted the Arab League to suspend its observer mission, Ban called for unity at the Security Council, which was to meet from 2000 GMT.
The Council, he said, must be "united this time, speak and act in a coherent manner, reflecting the wishes of the international community and reflecting the urgent wishes and aspirations of the Syrian people, who have been yearning for freedom."
"This is crucially important," Ban told a news conference in Amman hours before the Council meeting at which the Arab League was to appeal for backing for its plan for an end to the Syria crisis.
Clinton's office announced she was heading to New York to push for a UN resolution on Syria.
"The Security Council must act and make clear to the Syrian regime that the world community views its actions as a threat to peace and security," she said in a statement.
"The violence must end, so that a new period of democratic transition can begin."
Syria's foreign ministry fired back, saying "the aggressive American and Western statements against Syria are escalating in a scandalous manner," and again blaming the recent violence on "armed terrorist groups."
Russia and China - which have accused Western nations of misusing a UN mandate in their intervention to bring down Libyan dictator Muammar Gaddafi- vetoed a Western-backed draft resolution on Syria in October.
On Monday, Gatilov said Moscow would not back the latest draft, before adding on Tuesday that it was "the path towards civil war."
Russia has instead called for Assad's regime and the opposition to hold "informal contacts" in Moscow without any preconditions.
Asked about the initiative, the White House said it supported a political solution but was "intensely discussing" with Russia the "real deterioration on the ground."