Russia has rejected UN report that accuses Syrian government of using chemical attacks as "unconvincing and "full of contradictions".

The Organization for the Prohibition of Chemical Weapons (OPCW) and the UN’s Joint Investigative Mechanism (JIM) has compiled a report, alleging that Syrian forces have carried out three chlorine gas attacks on villages in 2014 and 2015.

The UN-led investigation said Syrian military helicopters, in one of the alleged attacks, dropped barrel bombs containing chlorine gas on the village of Qmenas, located in the northwestern province of Idlib in March 2015.

The report said it could not confirm who had command and control of the helicopter squadrons at the time.

Russian Ambassador to the UN Vitaly Churkin has referred to a host of irregularities and unsubstantiated claims and called the report "generally unconvincing."

He said the report fails to present solid evidence to support the claim, adding, "The report could not confirm the names of the individuals who had command and control of the helicopter squadrons at the time."

Churkin also said the investigators had neglected to mention Syrian government's explanations that the spill of chlorine might have been caused by a traffic accident as it was being transported to the village by militants.

He also urged the Syrian government to launch its own investigations regarding the claims.

Syria has been suffering a West-supported conflict since 2011.