US President Barack Obama urged Syrian President Bashar al-Assad to step down, saying he "must step aside and allow a democratic transition to proceed immediately."
Obama addressed the alleged night shelling of residential areas of the Syrian city of Homs by security forces, in which up to 260 civilians were reportedly killed. The incident is considered one of the bloodiest episodes of the uprising.
"I strongly condemn the Syrian government's unspeakable assault against the people of Homs and I offer my deepest sympathy to those who have lost loved ones," Obama said in a written statement.
The government in Damascus denied involvement in the Homs assault. According to UN estimates, over 5,400 people have lost their lives in almost 11 months of government crackdown on civilian protests.
He also said the UN Security Council had “an opportunity to stand against the Assad regime's relentless brutality and to demonstrate that it is a credible advocate for the universal rights that are written into the UN Charter."
Members of the Security Council were due to vote on Saturday on a draft resolution that would back an Arab League call for President Assad to step down. Amid recent talk that Russia would ask for a delay, Russian Foreign Minister Sergei Lavrov said that consensus was possible if Security Council members took a "constructive approach" to Russia's proposed changes.
Russia, and to a lesser extent China, have opposed any resolution that would advocate forced regime change or military intervention.
"If our colleagues display a constructive approach, we will get ... a collective Security Council resolution that I am certain all countries without exception will sign onto," he was quoted as saying by Itar-Tass news agency after meeting with US Secretary of State Hillary Clinton for security talks in Munich.
sb/msh (AP, AFP, Reuters, dpa)