AMSTERDAM –

Russia and Ukraine have accused each other at the global chemical weapons watchdog in The Hague of using banned toxins on the battlefield, the organization said on Tuesday.

The Organisation for the Prohibition of Chemical Weapons (OPCW) said that the accusations were “insufficiently substantiated” but added: “The situation remains volatile and extremely concerning regarding the possible re-emergence of use of toxic chemicals as weapons.”

Neither Russia nor Ukraine has formally asked the OPCW to investigate the alleged use of chemical weapons, it said.

Andriy Sybiha, Ukraine’s first deputy foreign minister, said he discussed Russia’s use of ammunition with chemicals on the battlefield with OPCW director Fernando Arias on Tuesday.

Sybiha informed Arias about the parliamentary ratification of an agreement that “opens up opportunities for organizing OPCW technical assistance visits to Ukraine”, the ministry said in a statement.

Last week, the U.S. said Russia had violated the international chemical weapons ban overseen by the OPCW by deploying the choking agent chloropicrin against Ukrainian troops and using riot control agents “as a method of warfare” in Ukraine.

It followed Ukrainian assertions in April that Russia had increased its use of tear gas in the trenches.

Ukraine’s General Staff said in a statement earlier this month its armed forces had recorded 1,891 cases of Russia using “ammunition equipped with dangerous chemical substances” in the year till April.

Russia has denied allegations of violating the Chemical Weapons Convention.

In documents posted on the OPCW website, Moscow accused Kyiv of using “a wide range of toxic chemicals against Russian servicemen and public officials,” including fertilizers, pesticides and other banned toxins.

The OPCW said it had been monitoring the situation since February 2022, when Moscow invaded Ukraine.

Under the Chemical Weapons Convention, any toxic chemical used with the purpose of causing harm or death is considered a chemical weapon.

“It is against the Convention to use riot control agents at war on the battlefield. If used as a method of warfare, these agents are considered chemical weapons and, hence, are prohibited under the Convention,” the OPCW said.

(Reporting by Anthony Deutsch in Amsterdam and Max Hunder in Kyiv. Editing by William Maclean, Gareth Jones and Nick Macfie)