- U.S. secretary of state: Russia has a "very consistent arms trade" with the Syrian regime
- Russia denies the claim and accuses others of pushing an agenda against al-Assad
- A U.N. council authorizes an independent probe into last week's massacre in Houla
(CNN) -- The Arab League is set to convene Saturday to discuss the Syrian crisis as world leaders quarrel over who is fueling the spiraling conflict.
Accused by the top U.S. diplomat of "propping up the regime" of Syria's embattled president, Russia struck back Friday by denying arms sales to Damascus and saying international efforts may have fueled instability and violence.
U.S. Secretary of State Hillary Clinton hammered home her claim Friday that Moscow is helping its longtime ally in Damascus through a "very consistent arms trade" that "has strengthened (President Bashar al-Assad's) regime."
"The fact that Russia has continued to sustain this trade in the face of efforts by the international community to impose sanctions and to prevent further arms flowing to the Assad regime, and in particular the Syrian military, has raised serious concerns on our part," Clinton said.
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Houla after the massacre, in the war zone Russian President Vladimir Putin responded hours later by flatly denying "any trading connections (or) military" with its longtime ally Syria.
"The only thing that concerns us in (Syria) is the possibility of radicalization of the situation, the situation getting out of control and the deaths of civilians," Putin said from France after meeting new French President Francois Hollande. "Our aim is to bring the conflict to peace."
But Russian Foreign Ministry spokesman A.K. Lukashevich spoke more forcefully Friday, asserting that some international efforts -- including threats of military intervention -- have exacerbated the crisis, bringing Syria closer to civil war and making it easier for "strong religious elements (to) come to the forefront."
Lukashevich accused "international and regional players" of pushing an agenda to get al-Assad ousted.
Hollande is among the corps of world leaders who say al-Assad must go.
"There will only be an exit possible with the departure of Bashar al-Assad," Hollande said.
Putin warned against the international community acting rashly, especially militarily.
"What happened in Libya and Iraq? ... Have they become safer and better? Where are they moving? Is there an answer? Nobody has it as of yet," Putin said. "That's why we're proposing, at least in Syria, to act carefully."
Meanwhile, the U.N. Human Rights Council on Friday authorized the U.N.'s Independent International Commission of Inquiry on Syria -- which has issued ongoing reports about violence in the country -- to conduct a robust probe into the Houla massacre last week that left 108 people dead, including 49 children.
Meeting in Geneva, Switzerland, 41 countries voted for the resolution while Russia, China and Cuba voted against it. Russia and China have vetoed U.N. Security Council attempts to formally condemn the al-Assad's government.
U.N. human rights chief Navi Pillay said the killings in Houla "may amount to crimes against humanity and other international crimes, and may be indicative of a pattern of widespread or systematic attacks against civilian populations that have been perpetrated with impunity."
Syria told Pillay's office that "terrorist armed groups" were responsible for Houla massacre. It said the military "was acting only in self-defense" and sought to protect civilians.
But opposition activists and residents have said pro-regime forces went house to house, lining up residents and shooting them.
More carnage spread across Syria on Friday, with at least 37 people slain across the country, the opposition Local Coordination Committees of Syria said.
The crisis in Syria began nearly 15 months ago when a tough government crackdown on protesters last year spiraled out of control and spawned a national anti-government uprising.
Fresh reports of terror have emerged this week. In the Homs province village of Bouyda, 12 factory workers were killed Thursday by pro-government gangs known as Shabiha, the opposition Syrian Observatory for Human Rights said. They were lined up against a wall and shot, the group said.
On the other side of the country, U.N. observers said the bodies of 13 people were discovered about 30 miles east of Deir Ezzor on Tuesday night.
CNN cannot independently confirm death tolls or reports of violence from Syria because the government limits access to the country by foreign journalists.
CNN's Joe Sterling, Holly Yan, Ivan Watson and Elizabeth Joseph contributed to this report.
