"There have been several allegations of chlorine attacks in Ghouta, in Idlib, and also now recently in Afrin. While we cannot independently verify these allegations, but if confirmed, it is outrageous and should have no impunity," UN Special Envoy for Syria Staffan de Mistura said.
The statement came shortly after US State Department spokeswoman Heather Nauert said the United States was alarmed over reports that the Syrian government had used chemical weapons near Idlib's city of Saraqib. Nauert also said Washington believed Russia was shielding the Syrian government from accountability for its alleged continued use of chemical weapons.
Staffan de Mistura reiterated Secretary-General Antonio Guterres' appeal to those fighting and all concerned "to de-escalate immediately and unconditionally." And he asked Russia, Iran and Turkey "to use their influence to help reduce violence."
Earlier in February, the UN-mandated Independent International Commission of Inquiry on the Syrian Arab Republic said it was investigating reports of the alleged use of chlorine in the Syrian provinces of Idlib and eastern Ghouta.
The Russian Defense Ministry has refuted the allegations, saying that the US claims were based on rumors and information from militants and that the accusations have never been proven with facts.