Liz Truss will hold Putin’s ‘regime’ accountable for using chemical weapons

The foreign minister has pledged to hold Vladimir Putin “and his regime” to account if it is proven that Russian forces used chemical agents in an attack on Mariupol. Liz Truss tweeted: “Reports that Russian forces may have used chemical agents in an attack on residents of Mariupol – we are urgently working with partners to verify details.

“Any use of such weapons would be a ruthless escalation in this conflict. We will hold Putin and his regime to account.

The city’s Azov regiment reported soldiers were stunned and unable to breathe after a “poisonous substance of unknown origin” was dropped on them by a Russian drone, according to the Daily Mail. It came hours after the mayor of Mariupol said more than 10,000 civilians had died in the Russian siege of his city and the death toll could top 20,000.

Britain is increasingly concerned that Russia could use white phosphorus munitions in the bombardment of the city. White phosphorus is used for night lighting or to create a smoke screen, but when deployed as a weapon it causes horrible burns.

Western officials believe Russia wants to bring about the fall of Mariupol both to free up troops for the fight in the Donbass, but also to create a route north for Kremlin forces as they seek to form a movement clamp on the Ukrainian defenders to the east. Officials have said Mr Putin will double or even triple the number of Russian troops in Donbass as the Russian president resorts to a “diminished” invasion strategy.

However, mustering troops will not necessarily give Moscow an advantage over Ukraine, as Kyiv forces have successfully pushed back insurgents in the east of the country. The Russian leader has been forced to ‘significantly scale down’ the plan in Ukraine, an official has said, amid suggestions that Mr Putin wants to take the Donbass region before May 9 – when Russia traditionally scores victory in the Soviet Union during World War II against Nazi Germany with military parades in Moscow.

Meanwhile, on Monday night, Ukraine’s parliament said Russian forces had fired on nitric acid tanks in Donetsk, with residents of the eastern city told to prepare “protective masks soaked in a soda solution “. The Foreign Ministry said it was “shocked” by reports of mass graves discovered in the village of Buzova, outside kyiv.

Buzova is near Bucha, another town where atrocities have been uncovered, although Russia has claimed scenes from the aftermath of its occupation were staged. The UK will work with its allies to “investigate war crimes and ensure justice is served”, a Foreign Office spokesperson said.

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