"This is quite an awful position, I cannot even find the words to make clear how we feel. This is directly justifying terrorism. How can this be understood?" Lavrov told reporters in Moscow.
Syria has been the scene of deadly unrest since mid-March, 2011 and many people, including large numbers of army and security personnel, have been killed in the violence.
The West and the Syrian opposition accuse the government of killing protesters. But Damascus blames ''outlaws, saboteurs and armed terrorist groups'' for the unrest, insisting that it is being orchestrated from abroad.