The president of the United Nations General Assembly says the number of people killed in the uprising in Syria is now more than 8000.
Nassir Abdulaziz al-Nasser says many of the victims are women and children and the international community must act.
He says the General Assembly is ready to take action if the Security Council fails to do so.
Foreign ministers are arguing over the degree of western intervention at a meeting of the United Nations Security Council.
UN secretary-general Ban Ki Moon is calling for a unified international response while British Foreign Secretary William Hague called on the UN to show some leadership and unity over finding a solution to the deepening crisis.
Mr Ban told the Security Council it had failed to act decisively.
He said it should be possible for the council to call for an immediate end to the brutal repression and violations of human rights.
US Secretary of State Hillary Clinton said the council should not remain silent when governments massacre their own people.
Meanwhile, United Nations-Arab League envoy Kofi Annan has held talks in Turkey with the opposition Syrian National Council.
He said they "promised their full co-operation, which will be necessary if we are going to succeed".