Russia on Thursday denied a U.S. accusation that its forces in Ukraine had violated an international ban on chemical weapons by using substances including a prohibited choking agent.

Kremlin spokesman Dmitry Peskov told reporters that Moscow remained bound by its obligations under the treaty that bans chemical weapons.

The United States on Wednesday accused Russia of violating it by deploying the choking agent chloropicrin against Ukrainian troops and using riot control agents "as a method of warfare" in Ukraine.

"As always, such announcements are absolutely unfounded and are not supported by anything. Russia has been and remains committed to its obligations under international law in this area," Peskov said.