The UN Human Rights Council will on Friday debate a call for an independent probe into the massacre in the Syrian town of Houla that triggered global horror and outrage.
Qatar, Turkey and the US have submitted a draft resolution to be considered at a special Rights Council session which condemns the "outrageous" killing of 49 children in Houla and calls for the perpetrators to be held to account.
The three nations want a "comprehensive, independent and unfettered special inquiry" to be carried out by the Commission of Inquiry on Syria, set up by the Rights Council last year to investigate rights abuses in the country.
Last week's massacre, which left at least 108 people dead including women and children, sparked outrage across the world and prompted many Western nations to expel their Syrian diplomats in protest.
The UN High Commissioner for Human Rights says most of the victims were summarily executed, and some UN officials have said there were suspicions of involvement by pro-government shabiha militiamen.
Damascus on Thursday insisted that a preliminary investigation showed "armed gangs" carried out the Houla killings.