UN member states have overwhelmingly voted to condemn the Syrian government at a special session of the General Assembly.

The 193-nation assembly approved the Saudi-drafted resolution, which expressed "grave concern" at the escalation of violence in Syria and condemned the Security Council for its action, with 133 votes in favor, 12 against and 31 abstentions.

Dozens of other countries, including many Western states, co-sponsored the resolution.

As expected, Mr Assad's staunch ally Russia was among the 12 countries that opposed the resolution in the assembly, where no country has a veto but all decisions are non-binding.

Others that voted against it included China, Iran, North Korea, Belarus, Cuba and others nations that often criticize the West. Some countries did not participate in the vote.

The resolution has the assembly "deploring the failure of the Security Council to agree on measures to ensure the compliance of Syrian authorities with its decisions".

It also calls for "an inclusive Syrian-led political transition to a democratic, pluralistic political system".

The US and European powers blame Russia for the deadlock on the 15-nation council.

Last month Russia and China joined forces in their third double veto on the Syrian crisis to strike down a resolution that would have called for an end to the violence and threatened Damascus with sanctions.

Many of the elements from the latest vetoed resolution were included in the text the assembly approved.

US Ambassador to the United Nations Susan Rice welcomed the resolution's adoption.

"Despite the continued opposition of an increasingly isolated minority, the overwhelming majority of UN members clearly stands resolutely with the Syrian people as they seek to fulfill their legitimate aspirations," Ms Rice said.

Syrian Ambassador Bashar Ja'afari, after the vote, complained that the meeting was "another piece of theatre" organised by the Qatari president of the General Assembly, Nassir Abdulaziz al-Nasser, to pursue his country's agenda.

Saudi Arabia and Qatar support the rebels determined to oust Assad. Mr Ja'fari repeated his country's accusations that both are supplying weapons to the opposition, adding that the "resolution will have no impact whatsoever."