Russia on Tuesday vetoed a UN Security Council draft resolution allowing the extension of the mission that investigates the use of chemical weapons in Syria.
It marked the ninth time Moscow has voted against a draft resolution on Syria presented before the Security Council.
Eleven countries voted in favor of the resolution while China and Kazakhstan abstained. Bolivia voted against it alongside Russia.
The investigation by the UN and the Organization for the Prohibition of Chemical Weapons, known as the Joint Investigative Mechanism (JIM), was created by the UN Security Council in August 2015 following reports of chemical attacks in Syria. It became fully operational in January 2016 and presented its first report in February that year.
The JIM's report on the use of chemical weapons in Syria is scheduled to be submitted to the Security Council on 26 October. Its mandate is to end on 17 November.
Reports of chemical attacks on civilian populations and opposition fighters have continued to come out of Syria since an attack in August 2013 killed more than 1,400 people in East Ghouta near Damascus.
The Syrian Network for Human Rights said it documented at least 174 chemical attacks in Syria since September 2013 when the Security Council issued resolution 2118 for the dismantling of Syria's chemical weapons arsenal.
The U.S. condemned Russia for its decision to veto the extension of the probe into Syria's chemical weapons use.
"We are disappointed. We are very disappointed that Russia put what it considered to be political considerations over the Syrian people who were so brutally murdered," US State Department spokeswoman Heather Nauert said during a daily press briefing.
UK Foreign Secretary Boris Johnson also condemned Russia's veto, saying he was "dismayed" at the decision, adding that the veto puts Russia "on the wrong side of the argument".