Activists say the death toll in Syria's civil war has topped 136,000 after January was one of the bloodiest months.
The prospects of a peaceful outcome look dim after 10 days of talks in Geneva yielded few tangible results and the regime said it was unsure whether it would return to the negotiating table.
The opposition British-based Syrian Observatory for Human Rights says the death toll includes almost 48,000 civilians, more than 7300 of them children.
The observatory said the real toll could be much higher because of the extreme secrecy of rebels, jihadists and the regime about casualty figures.
The conflict began after a regime crackdown on anti-government demonstrations, sparking an armed uprising against President Bashar al-Assad.
In addition to the dead and a much larger number of wounded, millions of people have been displaced internally and as refugees.