The U.N. Security Council may vote later Tuesday on a draft resolution condemning Syria's brutal crackdown on anti-government activists.

The European-drafted proposal threatens “targeted measures” against Syrian President Bashar al-Assad's government if it does not stop its deadly assault on pro-democracy demonstrators calling for his departure.

State Department spokeswoman Victoria Nuland said Tuesday the U.S. believes a strong Security Council resolution on Syria is “long overdue.” She said U.S. officials remain hopeful that the measure will get strong support.

Earlier Tuesday, Russia said it will not support the resolution because its wording is “unacceptable” The Interfax news agency quoted Foreign Minister Gennady Gatilov as saying the draft resolution leaves open the possibility of imposing sanctions on Syria, which Moscow opposes.

Meanwhile, Syrian activists say at least four people were killed on Tuesday in northwestern Syria in clashes between security forces and military defectors who support the opposition.

The clashes follow days of military operations in the central town of Rastan, where activists say government forces arrested as many as 3,000 people as part of a crackdown on dissent. Syria's official SANA news agency puts the number of arrests “in the dozens.”

Syria has been using military force to crush almost seven months of opposition protests demanding an end to Mr. Assad's 11-year autocratic rule.

The United Nations says at least 2,700 people have been killed in the crackdown.