With Russia promising to upend any United Nations Security Council resolution calling for Syria to halt its crackdown on anti-government activists, Secretary of State Hillary Clinton today challenged the Kremlin to make a stand.

Speaking at a signing ceremony with the foreign minister of Singapore, Clinton appealed to Security Council members to make their place known, asking, "Whose side are you on?

"Are you on the side of the Syrian people?" she asked. "Are you on the side of the Arab League?  Are you on the side of the people of the Middle East and North Africa who have during his past year spoken out courageously and often for their rights?"

Or, Clinton asked,  "Are you on the side of a brutal dictatorial regime?"

Chinese officials, like the Russians, have indicated they would veto any Security Council resolution that takes sides in what looks increasingly like a civil war in Syria.

Both Russia and China have lucrative business arrangements with the Assad government. Russia, in particular, sells military weapons and equipment to the Syrian government. It also keeps a naval base in Tartus, on Syria's west coast.

But the Arab League, which called off its monitoring mission this weekend, blames the recent escalation of violence on forces loyal to President Bashar al-Assad. The armed opposition, known as the Free Syrian Army, is made up of military defectors and other, more shadowy forces.

State Department spokesperson Victoria Nuland said at today's briefing that U.S. ambassador to the U.N., Susan Rice, is working with other members of the Security Council on the wording of a potential resolution.

There is still, however, no time frame for a vote.

"They've got some hard work to do in New York," Nuland said, and Clinton has still not been able to speak with Russian Foreign Minister Sergey Lavrov.

As for the U.S. embassy in Damascus, Syria, Nuland said it remains open.

"Our operations are open, but our concerns remain" about security, she said, because the Syrian government has still not provided the security measures specified by U.S. officials.