The United Nations Security Council has pushed back Wednesday's vote on Syria with hopes of persuading Russia into approving a resolution condemning the Bashar al-Assad regime that would also threaten sanctions if the Syrian government continues to use heavy weapons in towns and cities.

Russia has already said it would to veto the resolution, which was first proposed by Britain, the United States, France and Germany. China is expected to vote against the draft as well, which could reach the council as late as Friday.

Both Russia and China have blocked two earlier attempts to condemn the Assad regime, saying that the members of the Security Council were unfairly siding with the Syrian opposition.

The United States has tried to pressure Russia to cut ties with the Syrian government based on humanitarian grounds. Russian Foreign Minister Sergei Lavrov told U.S. Secretary of State Hillary Clinton in Moscow on Sunday that Moscow agreed that the situation on the ground is urgent, given the violence, but still hopes that diplomacy and negotiation will end the crisis that has so far killed 17,000 people.