The UK fears that Vladimir Putin’s forces could use white phosphorus (WP) munitions in the bombardment of the besieged Ukrainian port Mariupol.
A British defence intelligence assessment said WP had already been used by Russia in the Donetsk region of eastern Ukraine.
White phosphorus is used for illumination at night or to create a smokescreen, but when it is deployed as a weapon it causes horrific burns.
The intelligence assessment published by the Ministry of Defence on Monday said: “Russian forces’ prior use of phosphorus munitions in the Donetsk Oblast raises the possibility of their future employment in Mariupol as fighting for the city intensifies.”
The MoD said Russian forces had continued shelling in the Donetsk and Luhansk areas of eastern Ukraine, but Kyiv’s troops had repulsed “several assaults”.
“Russia’s continued reliance on unguided bombs decreases their ability to discriminate when targeting and conducting strikes while greatly increasing the risk of further civilian casualties,” the department warned.
The UK is set to step up its military support for Ukraine following Boris Johnson’s unannounced visit to see Volodymyr Zelensky in Kyiv over the weekend.
Cabinet minister George Eustice told Sky News: “We must ensure that Putin cannot prevail on this.
“The Ukrainians have been incredibly brave, I think President Zelensky has led his people well and we’ve all been humbled really by the acts of bravery we’ve seen, but also deeply shocked about some of those terrible scenes that we’re seeing coming out now from the cities from which Russia’s withdrawn.”
In the village of Buzova outside Kyiv, local officials said bodies showing “evidence of execution” had been discovered following the Russian withdrawal.
Buzova is near Bucha, another town where atrocities were discovered – although Russia has claimed the scenes from the aftermath of its occupation were staged.
Mr Zelensky used his nightly address to warn Ukrainians to brace for a Russian onslaught in the country’s east.
“Russian troops will move to even larger operations in the east of our state,” he said.
“They can use even more missiles against us, even more air bombs. But we are preparing for their actions.
“We will respond. We will be even more active in providing Ukraine with weapons.”
