Russia and China vetoed on Saturday a UN resolution that backed an Arab plan calling on Syrian President Bashar al-Assad to quit, stalling global efforts to end his bloody crackdown on unrest after hundreds were reported killed in the city of Homs.
The high-level diplomatic setback came after world leaders and Syrian opposition activists accused Assad's forces of a massacre in a sustained shelling of Homs, the bloodiest episode in 11 months of upheaval in the pivotal Arab country.
Russia and China joined in a double veto of a Western- and Arab-driven resolution at the U.N. Security Council endorsing the Arab League plan for Assad to hand power to a deputy to make way for a transition towards democracy.
The other 13 council members voted for the resolution that would have said the council "fully supports" the League plan aimed at stopping Syria's bloodshed, whose sectarian overtones threaten stability in the wider Middle East region.
Russia complained that the draft resolution was an improper and biased attempt at "regime change" in Syria, which is Moscow's sole major Middle East ally, an important buyer of Russian arms exports and host to a Russian naval base.
With an eye to events in Homs, U.S. Ambassador to the United Nations Susan Rice dispensed with the usual diplomatic courtesies and declared she was "disgusted" by the Russian-Chinese veto, adding that "any further bloodshed that flows will be on their hands".
Shortly before the Security Council voted, US President Barack Obama denounced the "unspeakable assault" on Homs, demanded that Assad leave power immediately and called for U.N. action against Assad's "relentless brutality".
"Any government that brutalizes and massacres its people does not deserve to govern," Obama said.
He and other Western and Arab leaders exerted unprecedented pressure on Russia to allow the Security Council to pass the Arab League-backed resolution that calls for Assad to relinquish his autocratic powers and end the violence. The world body says over 5,000 civilians have been killed.
But Russia, and China following Moscow's lead, weighed in to torpedo U.N. action on Syria for the second time in four months. In October, they vetoed a European-drafted resolution condemning Syria and threatening it with possible sanctions.
U.S. Secretary of State Hillary Clinton said it had not been possible to work constructively with Russia ahead of the vote, even though military intervention in Syria - fiercely opposed by Moscow - had been absolutely ruled out.
"I thought that there might be some ways to bridge, even at this last moment, a few of the concerns that the Russians had. I offered to work in a constructive manner to do so. That has not been possible," she told reporters at a Munich conference.
Clinton warned that the risk of more bloodshed and civil war in Syria had risen after the collapse of the U.N. resolution.
French President Nicolas Sarkozy said after the vote that France was consulting with Arab and European countries to create a contact group on Syria to try to find a solution to the crisis .
"France is not giving up," Sarkozy said in a statement, saying Paris was in touch with Arab and European partners to create a "Friends of the Syrian People Group" that would marshal international support to implement the Arab League plan.
The uprising pits Syria's majority Sunni Muslims against Assad's minority Alawites, an offshoot of Shi'ite Islam, who have dominated the country's power structure for decades.
After what U.S. officials called "vigorous" talks between Clinton and Foreign Minister Sergei Lavrov, Moscow announced that he and its foreign intelligence chief would fly to Syria on Tuesday to meet Assad, although the trip's goal was not given.
Moscow objected that the resolution contained steps against Assad, but not against his armed opponents, Lavrov said in Munich before the vote. "Unless you do it both ways, you are taking sides in a civil war."
In New York, Western delegations rejected what they called "wrecking amendments" by Russia to add language blaming the opposition along with the government for violence and diluting calls for Syria to withdraw its security forces from cities.
Russian Ambassador Vitaly Churkin denied that Moscow's amendments were last-minute, or that Russia was standing in the way of a peaceful resolution of the crisis.
"Some influential members of the international community, unfortunately, including those sitting around this table, from the very beginning of the Syrian process have been undermining the opportunity for a political settlement," Churkin said.
Syrian U.N. envoy Bashar Ja'afari criticized the resolution and its sponsors, which included Saudi Arabia and seven other Arab states, saying nations "that prevent women from attending a soccer match" had no right to preach democracy to Syria.
He also denied that Syrian forces killed hundreds of civilians in Homs, saying that "no sensible person" would launch such an attack the night before the Security Council was set to discuss his country.