Syrian government forces reasserted control of Damascus suburbs on Tuesday after beating back rebels at the capital's doorstep and Russia warned that an international effort to resolve the conflict could instead lead to civil war.

Western and Arab diplomats piled more pressure on Syrian President Bashar Assad, pushing for a UN Security Council resolution which would call for him to step down to defuse the 10-month-old uprising against his family's dynastic rule.

They will make the case for a resolution adopting the Arab League power transfer plan on Tuesday, with U.S. Secretary of State Hillary Clinton, French Foreign Minister Alain Juppe and Britain's William Hague presenting a united western front.

The resolution's fate depends on whether the Arabs and their Western backers can persuade Russia not to veto it.

But a senior Russian diplomat said in Moscow the move would only set the stage for civil war, Interfax news agency reported.

"The Western draft Security Council resolution on Syria will not lead to a search for compromise," it quoted Deputy Foreign Minister Gennady Gatilov as saying. "Pushing it is a path to civil war."

On the battlefront, activists in eastern districts of Damascus said troops fired in the air as they advanced beyond areas from which the defector Free Syrian Army withdrew, capping three days of fighting activists said killed at least 100 people. Tanks also swarmed into the area.

"The suburbs are under an unannounced curfew. A small groceries shop opened this morning and soldiers came and beat the owner and forced him to shut down," said an activist in the Ain Tarma neighbourhood on Tuesday.

Others said residents of some eastern districts were allowed to flee their neighborhoods in vehicles by advancing troops.

Events on the ground are difficult to confirm as the Syrian government restricts most access by journalists.

Activist groups said 25 people were killed on Monday in Damascus suburbs and dozens more died in other parts of the country, mostly in raids in and around the central city of Homs, which has seen some of the heaviest attacks by Assad's forces.

Government troops were on the move as Arab League Secretary-General Nabil Elaraby and the prime minister of Qatar readied the appeal to the Security Council to back their call for Assad to quit power and prepare for elections.

The uprising against Assad - one of the most violent revolts of the "Arab Spring" - has entered a new phase in recent weeks, with an insurgency whose leadership is based in Turkey daring to show its face at the outskirts of the capital.

A last-ditch bid by Moscow to broker talks between Assad's government and rebels foundered when the opposition refused to attend, citing the continued killing, torture and imprisonment of the president's opponents.

Washington said countries needed to accept that Assad's rule was doomed and stop shielding him in the Security Council.

"As governments make decisions about where they stand on this issue and what further steps need to be taken with regards to the brutality of the Assad regime it is important to calculate into your considerations the fact that he will go," White House spokesman Jay Carney said on Monday.

"The regime has lost control of the country and will eventually fall."

Syria dismissed the U.S. remarks.

"We are not surprised at the lack of wisdom or rationality of these statements and regret that they are still issued by countries that are used to making the Middle East an arena for their follies and failures," the state news agency quoted a Foreign Ministry source as saying.

A draft of the UN Security Council resolution, obtained by Reuters, calls for a "political transition" in Syria, and says the Security Council could adopt unspecified further measures if Syria does not comply with its terms.

It endorses the Arab League power transfer plan. So far Moscow has shown little sign of being persuaded to let it pass.

Nevertheless, some Western diplomats said they hoped Russia and China could be persuaded not to block the draft. Their abstention last March paved the way for the Council authorization that eventually helped topple Muammar Gadhafi in Libya.

Assad's forces appear to have decisively beaten back an attempt by the opposition to assert themselves on the outskirts of Damascus.

Activists and residents said Syrian troops took complete control of Hamourieyeh and other eastern districts after rebels appeared as close as 8 km (5 miles) to Damascus.

An activist said the defector force - which has links to Syria's divided formal opposition - mounted scattered attacks on government troops who advanced through the district of Saqba, held by rebels just days earlier.

Their forays near the capital follow a negotiated victory in Zabadani - a town of 40,000 in mountainous near the border with Lebanon - after government forces pulled back under a cease-fire.

Some rebel commanders have spoken of creating "liberated" territories to force diplomatic action.

Bloodshed and unrest are not confined to the capital.

Homs residents said fighting erupted on Monday in the al-Qusour neighborhood, and several armored vehicles belonging to loyalist forces were destroyed.

In the northern commercial hub of Aleppo - relatively quiet in the uprising as an alliance between Assad and the town's Sunni Muslim merchant elite - demonstrations have erupted in several districts since pro-Assad militiamen killed 10 people following a pro-democracy demonstration on Friday.

Security forces cut off electricity from Fardos neighborhood of Aleppo and arrested 100 youths on Monday after a demonstration demanding the removal of Assad, activists said.

Syria's state news agency said six soldiers died in an attack near Deraa in the south and a gas pipeline was blown up on Monday. The state news agency has reported funerals of more than 70 members of the security forces members since Friday.

Since the Arab League suspended its monitoring mission in Syria owing to rising violence, the prospects for a negotiated end to the bloodshed have dimmed.

Senior members of the main opposition council rejected Russian-brokered talks that Moscow said Syria had accepted. They argued he must go.

The United Nations said in December more than 5,000 people had been killed in the protests and crackdown. Syria says more than 2,000 security force members have been killed by militants.