NEW DELHI: The United States accused Russia of having used "the chemical weapon chloropicrin against Ukrainian forces" in violation of the Chemical Weapons Convention.

The statement from the US State Department further alleged that Moscow has also been using "riot control agents (tear gas) as a method of warfare in Ukraine, also in violation of the CWC."

The statement also details US sanctions against more than 280 individuals and entities "to impose additional costs on Russia for both its foreign aggression and internal repression."

Furthermore, it adds that among these are more than 80 entities and individuals, "including those engaged in the development of Russia’s future energy, metals, and mining production and export capacity; sanctions evasion and circumvention; and furthering Russia's ability to wage its war against Ukraine."

The statement asserts that the use of such chemical weapons is far from an "isolated incident" and "is probably driven by Russian forces' desire to dislodge Ukrainian forces from fortified positions and achieve tactical gains on the battlefield."

Slamming Moscow, the statement further states, "Russia's ongoing disregard for its obligations to the CWC comes from the same playbook as its operations to poison Aleksey Navalny and Sergei and Yulia Skripal with Novichok nerve agents."

Determining the illegal use of chemical weapons and riot weapons, America said it was imposing sanctions on three Russian state entities linked to Moscow's development of chemical and biological weapons. One of the entities is a specialised military unit that reportedly facilitated the use of chloropicrin against Ukrainian troops.

Furthermore, four Russian companies that support the three entities were also sanctioned.

Separately, the US Treasury has imposed sanctions on three entities and two individuals who were involved in buying items for Russian military institutes linked to the country's chemical and biological weapons programmes.

These sanctions freeze any US-based assets belonging to the sanctioned entities and generally prohibit Americans from doing business with them.

Chloropicrin is classified as a banned choking agent by the Organization for the Prohibition of Chemical Weapons (OPCW). The Hague-based organisation as per Reuters, was established to enforce and oversee compliance with the Chemical Weapons Convention (CWC) of 1993.

One of the earliest instances of the use of this banned chemical weapon was during World War I when German forces fired it against Allied troops.