In a separate development, Kuwait will host an international conference next month to address to Syrian crisis, the ruling emir said on Monday, as foes of Assad voiced frustration with international efforts to end the civil war.

In Damascus, the Syrian opposition vented its anger at what it called a "silence" over the unabated killing of civilians by government forces, most recently in the central town of Halfaya.

Assad is under growing pressure from rebel forces in the 21-month war that activists say has killed more than 44,000 people.

Kuwait's emir, Sheikh Sabah al-Ahmad al Sabah, said the conference for Syrian donors would be held in late January in response to an invitation by UN Secretary-General Ban Ki-moon.

"The Syrian wound is still bleeding, and the killing machine still continues, killing dozens of our brothers in Syria each day", the emir said at a meeting of the Gulf Cooperation Council in Bahrain.

Last week, the United Nations appealed for $1.5 billion to help save the lives of millions of Syrians suffering in a "dramatically deteriorating" humanitarian situation. The appeals are to help 4 million people within Syria and up to 1 million Syrian refugees in five other countries until next July.

Xinhua-Reuters

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