China hit back on Saturday at criticism of its stance over the crisis in Syria following a vote at the United Nations which overwhelmingly condemned the Syrian government, repeating Beijing's position that outside interference will not help.

The special session of the 193-nation U.N. General Assembly approved on Friday the Saudi-drafted resolution, which expressed "grave concern" at the escalation of violence in Syria and condemned the Security Council for its inaction.

As expected, Syria'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 criticise the West.

Western diplomats said the vote highlighted the isolation of Syrian President Bashar al-Assad's supporters Russia and China.

Speaking at a hastily arranged news conference in Beijing, Wang Kejian, deputy head of the Chinese Foreign Ministry's West Asian and North African Affairs Department, said China continued to support efforts at a peaceful, political solution for Syria.

"We should not easily close the window to a political solution let alone start military intervention," Wang said.

"China understands the desire of Arab countries and the Arab League for a swift resolution of the Syrian crisis.

"We have on numerous occasions stressed to various parties that the legitimate demands and aspirations of the Syrian people for change and for safeguarding their interests deserve respect," Wang said.

"The Syrian government should adopt concrete measures to respond to these demands and requests. We have repeatedly stressed that the future and destiny of Syria should be determined by the Syrian people independently.

"Those countries which have made unfounded criticism about China's position on Syria ... have, in pursuit of their own geopolitical interests in Syria, tried to hinder or undermine the political settlement process and are trying to shift responsibility for the difficulties onto other countries," he added.

Russia and China voted down a Security Council resolution on Syria last month, the third time the two countries have used their veto power to block resolutions designed to isolate Assad and end the 16-month conflict that has killed thousands.