Russia has abandoned a move by its United Nations ambassador to expand a probe of chemical weapons use by groups fighting in Syria to include Iraq.
U.S. and German government sources say they have found evidence that the Islamic State (IS) group used mustard gas and other chemical weapons in attacks on Iraqi Kurds this year.
The reports had prompted Russian UN Ambassador Vitaly Churkin to urge the UN Security Council to expand a planned investigation into who is responsible for chemical weapons use in Syria to include incidents of gas attacks in Iraq.
But UN diplomats said Iraq opposed broadening the mandate to include its territory, so Churkin backed off, enabling the Security Council to give final clearance to begin the investigation in Syria on September 10.
Several diplomats said Moscow may have also delayed the probe out of concern it might confirm allegations that the Syrian government used chemical weapons.
The government has denied that, but the United States and other Western states contend it is to blame, especially for barrel bombs containing chlorine and other toxic agents dropped by helicopters. The opposition doesn't have aircraft.