The United Nations human rights council on Friday extended the mandate of its investigation into war crimes in Syria by another six months.
It also condemned widespread violations by Syrian government forces in the 18-month-old conflict.
The 47-member Geneva forum adopted a resolution submitted by Arab states by a vote of 41 states in favor, with three states - China, Cuba and Russia - against and three abstentions.
Syria's ambassador Faysal Khabbaz Hamoui rejected the text as "highly-politicized and selective" and accused Islamic "terrorists" of fueling the violence in his country.
Since it was set up a year ago, the independent inquiry led by Brazilian Paulo Pinheiro has interviewed more than 1,100 victims, refugees and defectors but has been denied access to Syria.
"The work of the commission of inquiry is important because as they continue to document the names of individuals responsible for these crimes and violations, they help ensure that this will not be a case where impunity prevails, but rather that those responsible for crimes against the Syrian people will face justice and accountability," U.S. ambassador Eileen Chamberlain Donahoe told the talks.