Russia stood firm in the face of growing international pressure for tougher action over Syria, rejecting military intervention and questioning sanctions as fears of civil war grew.
And as world leaders Friday voiced fears the violence-wracked nation stood on the brink of civil war, the UN Human Rights Council ordered an independent probe to hunt those guilty of last week's massacre in Houla.
The London-based Syrian Observatory says as many as 2,300 of the more than 13,400 people killed since the uprising against Bashar al-Assad's regime began in March last year have died since April 12.
But despite the relentless violence, there are sharp differences between Arab and Western governments and Damascus allies Beijing and Moscow on the way forward.
Russian President Vladimir Putin, who met separately with German Chancellor Angela Merkel and French President Francois Hollande, warned the situation in Syria was "extremely dangerous" and said he saw emerging signs of a civil war.
But he struck a fiery tone in a joint press conference with Hollande, saying "sanctions hardly ever work in an efficient manner" and indicating that Bashar al-Assad's departure would not in itself resolve the crisis.
"What is happening in Libya? What is happening in Iraq? Has it become safer there?" he said in Paris. "We propose to act in an accurate, balanced manner at least in Syria."
But Hollande kept up the pressure for decisive action, insisting that Assad's departure was "a prerequisite for a political transition" and that "there must be sanctions" against his regime.
"Bashar al-Assad's regime has conducted itself in an unacceptable and intolerable manner. It has committed acts that disqualify itself" from governing, said Hollande.
Earlier, Merkel and Putin found common ground on backing the peace mission of UN-Arab League envoyKofi Annan but the former UN chief himself admitted to frustration at the slow progress he was making in staunching the bloodshed.
After his talks in Berlin, the Russian president underlined his opposition to military intervention to stop the bloodshed.
"You cannot do anything by force," Putin told reporters.
He also hit back at suggestions Moscow was supplying arms for use in Syria. "As far as arms supplies are concerned, Russia does not supply the weapons that could be used in a civil conflict," Putin said.
US Secretary of State Hillary Clinton, however, charged that Russia has continued to supply arms to the regime of Syrian President Assad.
"We know there has been a very consistent arms trade, even during the past year, coming from Russia to Syria" and that this had strengthened the Assad regime, she said in Oslo.
In Geneva, the Human Rights Council ordered an independent probe to hunt those guilty of the massacre in Houla that rights chief Navi Pillay said could constitute a "crime against humanity".
Forty-one of the 47-member council backed a call urging an investigation by the Commission of Inquiry on Syria, set up by the council last year to gather evidence on alleged rights abuses.
Russia, China and Cuba voted against the resolution, which they said was "unbalanced" as it presumed the guilt of the Syrian authorities for the May 25 massacre of 108 people, mostly children and women, in the central Syrian town.
Speaking in Lebanon, Annan spoke of his frustration at the slow progress in implementing his six-point peace plan that was supposed to begin with a ceasefire from April 12 but that has been violated daily.
"We are all impatient and frustrated over the violence, over the killings. I am frustrated even more maybe than most of you," said Annan.
"Bold action has to be taken by President Assad in Syria to put real energy into the implementation of the six-point peace plan."
But the rebel Free Syrian Army said the Annan plan had failed and announced that it would resume "defensive operations" after the expiry of a noon (0900 GMT) ultimatum for the regime to adhere to the plan.
FSA spokesman Kassem Saadeddine told AFP that "we will not go on the offensive because we do not want to be singled out as the ones responsible for breaking the peace initiative."
China's ambassador to the United Nations in Geneva Liu Zhenmin told the rights council meeting that an immediate ceasefire was necessary, otherwise the situation could lead "perhaps even to civil war."
And after talks with UN chief Ban Ki-moon in Istanbul, British Foreign Secretary William Hague voiced similar concerns.
"Both the secretary general and I -- and also the opposition in Syria -- think that Syria is on the edge of a catastrophic situation... on the edge of an all-out civil war and the collapse of Syria into sectarian strife," Hague said.
The Syrian Observatory for Human Rights said at least another 45 people, including 12 soldiers and eight people in the Damascus region, were killed across the country.
The UN ceasefire observer mission in Syria is now at "full strength," with nearly 300 military monitors in the conflict-stricken country, a UN peacekeeping spokesman said Friday.