BEIRUT — Syrian forces pushed dissident troops back from the edge of Damascus in heavy fighting Monday, escalating efforts to take back control of the capital's eastern doorstep ahead of key U.N. talks over a draft resolution demanding that President Bashar Assad step aside.
Gunfire and the boom of shelling rang out in several suburbs on Damascus' outskirts that have come under the domination of anti-regime fighters. Gunmen — apparently army defectors — were shown firing back in amateur videos posted online by activists. In one video, a government tank on the snow-dusted mountain plateau towering over the capital fired at one of the suburbs below.
As the bloodshed increased, with activists reporting more than 40 civilians killed Monday, Western and Arab countries stepped up pressure on Assad's ally Russia to overcome its opposition to the resolution.
U.S. Secretary of State Hillary Rodham Clinton and the British and French foreign ministers were heading to New York to push for backing of the measure during talks Tuesday at the United Nations.
"The status quo is unsustainable," Clinton said, saying the Assad regime was preventing a peaceful transition and warning that the resulting instability could "spill over throughout the region."
The draft resolution demands that Assad halt the crackdown and implement an Arab peace plan that calls for him to hand over power to his vice president and allow creation of a unity government to pave the way for elections.
If Assad fails to comply within 15 days, the council would consider "further measures," a reference to a possible move to impose economic or other sanctions.
British Prime Minister David Cameron called the situation in Syria "appalling" and appealed Monday to Russia to back the U.N. Security Council resolution.
"It is time for all the members of U.N. Security Council to live up to their responsibilities instead of shielding those who have blood on their hands," Cameron said.
Moscow, which in October vetoed the first council attempt to condemn Syria's crackdown, has shown little sign of budging in its opposition. It warns that the new measure could open the door to eventual military intervention, the way an Arab-backed U.N. resolution led to NATO airstrikes in Libya.
A French official said the draft U.N. resolution has a "comfortable majority" of support from 10 of the Security Council's 15 members, meaning Russia or China would have to use its veto power to stop it. The official said Russia had agreed to negotiate on the draft, but it was not yet clear if it would be willing to back it if changes were made.
The official spoke on condition of anonymity in accordance with department rules.
The Kremlin said Monday it was trying to put together negotiations in Moscow between Damascus and the opposition. It said Assad's government has agreed to participate; the opposition has in the past rejected any negotiations unless violence stops.
Western countries cited the past week's escalation in fighting to pressure Moscow.
"Russia can no longer explain blocking the U.N. and providing cover for the regime's brutal repression," a spokeswoman for British Prime Minister David Cameron said, on customary condition of anonymity in line with policy.
The United Nations estimated several weeks ago that more than 5,400 people have been killed in Syria's crackdown on the uprising against Assad's rule, which began in March. It has been unable to update the figure, and more than 200 people have been killed in the past five days alone, according to activists' reports.
Pro-Assad forces have fought for three days to take back a string of suburbs on the eastern approach to Damascus, mostly poorer, Sunni-majority communities. In past weeks, army defectors — masked men in military attire wielding assault rifles — set up checkpoints in the communities, defending protesters and virtually seizing control.
Late Sunday, government troops retook two of the districts closest to Damascus, Ein Tarma and Kfar Batna, said Rami Abdul-Rahman, the London-based head of the Syrian Human Rights Observatory, which tracks violence through contacts on the ground.
On Monday, the regime forces were trying to retake the next suburbs out, pounding neighborhoods with shelling and heavy machine guns in the districts of Saqba, Arbeen and Hamouriya, he said.
At least five civilians were killed in the fighting near Damascus, according to the Observatory and another activist group, the Local Coordination Committees.
Regime forces also heavily shelled buildings and battled dissidents in the central city of Homs, one of the main hot spots of the uprising, activists said.
The Observatory reported 28 killed in the city Monday. The Local Coordination Committees put the number at 27.
The reports could not be independently confirmed. Syrian authorities keep tight control on the media and have banned many foreign journalists from entering the country.
The Syrian Interior Ministry, in charge of security forces, said Monday that its three-day operation in the suburbs aimed to track down "terrorist groups" that have "committed atrocities" and vowed to continue until they were wiped out. Damascus had remained relatively quiet while most other Syrian cities have slipped into chaos since the uprising began.
Regime forces, backed by tanks and armored vehicles, heavily outgun and outnumber the defectors, organized into a force known as the Free Syrian Army. However, the military can't cover everywhere at once, and when it puts down the dissidents in one location, they arise in another. The dissidents' true numbers are unknown.
The result has been a dramatic militarization of a crisis that began with peaceful protests demanding the ouster of the Assad family and its regime. The army defectors began by protecting protesters, but over the weeks they have gone more on the offensive.
The dissidents have seemed increasingly confident in hit-and-run attacks.
On Monday, they freed five imprisoned comrades in an assault on a military base in the northeastern province of Idlib, the Observatory and Local Coordination Committees reported. Other defectors attacked a large military checkpoint outside Hama, destroying several transport trucks and claiming to kill a number of troops, the two groups said.
Six government soldiers were killed in an ambush on their vehicles in the southern region of Daraa, the state news agency SANA reported. The Observatory reported two other soldiers and 10 defectors killed in fighting elsewhere.
Attackers also blew up a gas pipeline near the border with Lebanon, SANA reported, the latest in numerous attacks on Syria's oil and gas infrastructure.
Because of the upsurge in violence, the Arab League halted a month-old observer mission, which had already come under heavy criticism for failing to stop the crackdown. The League turned to the U.N. Security Council to throw its weight behind its peace plan, which Damascus has rejected.
The move resembles the turn of events before last year's NATO air campaign in Libya, when Western countries waited for Arab League support before winning U.N. cover for intervention.
But so far, there has been little appetite for a similar campaign in Syria. There is no clear-cut geographical divide between the regime and its opponents as there was in Libya, and the opposition is even more divided and unknown than it was in the North African nation. Syria is intertwined in alliances with Iran, Hezbollah and Palestinian militant groups, and borders Israel — making the fallout from military action more unpredictable.
AP correspondents Bradley Klapper in Washington and Jamey Keaten in Paris contributed to this report.