The United States accused Russia on Monday of delaying the adoption of a UN Security Council condemnation of reported chlorine gas attacks in Syria that left many injured in recent days, including children.
US Ambassador Nikki Haley told the council that there was "obvious evidence from dozens of victims" to corroborate the chlorine attacks in rebel-held Eastern Ghouta.
"Now we have reports that the Assad regime has used chlorine gas against its people multiple times in recent weeks, including just yesterday," Haley said.
The United States has proposed a draft statement condemning the use of chemicals as a weapon but Russia requested that adoption be delayed to provide comments, diplomats said.
"Russia has delayed the adoption of this statement - a simple condemnation of Syrian children being suffocated by chlorine gas," she said.
The draft statement, obtained by AFP, condemns "in the strongest terms" the reported February 1 chlorine attack in the al-Malab neighborhood of the town of Douma that injured over 20 civilians including children.
The council expresses grave concern over three reported chlorine attacks in Eastern Ghouta in recent weeks and asserts that those responsible for using chemical weapons must be held accountable, according to the draft.
The council met to discuss chemical weapons use in Syria after Russia used its veto power twice in November to block the renewal of a UN investigative panel tasked with identifying those responsible for the deadly gas attacks.
Russia last month put forward a draft resolution to establish a new investigation but Western diplomats have raised questions about the impartiality of the proposed panel.
"This is not an impartial mechanism. It is a way to whitewash the findings of the latest investigation that Russia desperately wants to bury," Haley told the council.
The previous probe, vetoed by Russia, had found that Syrian forces were responsible for the April 2016 sarin attack on the rebel-held town of Khan Sheikhun, that killed scores of people.
The panel, known as the Joint Investigative Mechanism (JIM), also found that President Bashar al-Assad's forces used chlorine in two attacks on rebel-held villages in 2014 and 2015.
It also found that Islamic State (IS) jihadists had used mustard gas in 2015.