Russia and China have been condemned for vetoing a UN Security Council resolution to refer the Syrian crisis to the International Criminal Court (ICC) for a probe into possible war crimes.

In a move deemed as "callous" and disgraceful by Amnesty International and Human Rights Watch, the two Assad allies have used their veto power as permanent council members for the fourth time to push back any action against the Syrian regime.

The French-backed resolution, which did not specifically target either the government or the opposition, was signed by more than 60 countries and approved by the other 13 Security Council members. It condemned the "widespread violation" of human rights and international humanitarian law by Syrian authorities as well as abuses and violations by "non-state armed groups" in the last three years.

UN deputy secretary-general Jan Eliasson urged council members to find unity and "put an end to this long nightmare". But Russian Ambassador Vitaly Churkin joked with reporters that he was "going to be boringly predictable", and called the resolution a "publicity stunt".

Since Syria is not part of the Rome Statute that set up the ICC, the only way it can be referred to The Hague tribunal is by the Security Council. Syria UN Ambassador Bashar Ja'afari delivered a letter asking countries not to support the resolution and claimed the proposal was "biased" and an effort to "sabotage any chance of peaceful settlement of the Syrian crisis led by the Syrian people themselves". The only time the Security Council has agreed on Syria was on the disposal of chemical weapons and to demand access for the delivery of humanitarian aid. However, the terms of the latter are being openly flouted.

Amnesty International called the vetoes a "callous political move that betrays suffering people in Syria", while Human Rights Watch branded Russia and China's vote for "continued impunity" a "disgrace".