US does not know who used chemical weapons in Syria
The US still does not have enough evidence to say who used chemical weapons in Syria, US Acting Under Secretary of State for Arms Control and International Security Rose Gottemoeller said on Echo of Moscow radio station on Saturday.
An incident in which chemical weapons were apparently used occurred in Aleppo on March 19.
The Syrian government claimed that it was the opposition that used chemical weapons and asked the UN to investigate this.
The opposition insisted that chemical weapons had been used by the government forces.