The Pentagon is tracking reports of a potential Russian chemical weapons attack in Mariupol.

• Liz Truss, the British Foreign Secretary, is working "urgently" to confirm the details of an alleged chemical weapons attack on the residents of Mariupol, a besieged city in Ukraine.
• The Pentagon spokesperson stated that the reports were not verified, but they mirror U.S. worries about Russia's ability to employ a range of riot control agents, including tear gas combined with toxic substances, in Ukraine.
• If NATO members were to discover that Russia had used chemical weapons in the strategic holdout city, it would represent a major escalation of the conflict and present a direct challenge to NATO members.

The Pentagon is closely monitoring reports of a possible Russian chemical weapons attack on the besieged Ukrainian city of Mariupol, according to Defense Department press secretary John Kirby.

If NATO determines that Russia employed chemical weapons in the strategic stronghold, it would signify a significant intensification of the conflict and necessitate a direct response from NATO.

Kirby stated on Monday that there have been reports on social media suggesting that Russian forces may have used a chemical weapon in Mariupol, Ukraine, but they cannot confirm it yet and will closely monitor the situation.

Kirby stated that the reports, if accurate, are alarming and indicate our longstanding concerns about Russia's ability to employ a range of riot control agents, including tear gas combined with chemicals, in Ukraine.

Liz Truss, the British Foreign Secretary, stated that her government is working "urgently" to verify the details of an alleged attack.

The Azov Regiment, a Ukrainian National Guard unit, reported that Russian forces employed an unknown poisonous substance in their operations.

Truss tweeted that the use of such weapons would be a callous escalation in the conflict and that Putin and his regime would be held accountable.

Officials in the U.S. have been cautioning for multiple days that the Russian military will likely continue to perpetrate "atrocities" as it intensifies its assaults in eastern Ukraine.

Earlier in the day Monday, Kirby stated that Russian leaders have demonstrated their brutal approach to operations, using chemical weapons in Syria as an example, according to him.

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