Russian forces pushing their grinding offensive in eastern Ukraine "appear to be" resorting to World War I-era chemical weapons in their bid to dislodge Kyiv's defending units, according to the latest battlefield update from the Institute for the Study of War.

Colonel Oleksandr Shtupun, the spokesperson for the Tavria Ukrainian military group operating on the southeastern front line, said on Tuesday that Russian forces had been using "K-51 grenades with chloropicrin" in their attacks on Kyiv's positions.

In May 2024, the United States imposed new sanctions on three Russian government entities and four Russian companies in response to its full-scale war and use of chemical weapons against Ukraine.