Ukraine forces pushed back from key industrial city

Ukraine said Monday its forces had been pushed back from the centre of key industrial city Severodonetsk, where President Volodymyr Zelenskyy described a fight for "literally every metre".

The cities of Severodonetsk and Lysychansk, which are separated by a river, have been targeted for weeks as the last areas still under Ukrainian control in the eastern Lugansk region.

Regional governor Sergiy Gaiday said Monday Russian forces were "gathering more and more equipment" to "encircle" Severodonetsk, and that they had "pushed our troops from the centre and continue to destroy our city".

The local Azot chemical plant, where hundreds of civilians have reportedly taken refuge, was being "heavily shelled", Gaiday said.

In Lysychansk, bombardments killed three civilians, including a six-year-old boy, he said.

Severodonetsk had been "de facto" blocked off after Russian forces blew up the "last" bridge connecting it to Lysychansk Sunday, Eduard Basurin, a representative for pro-Russian separatists, said Monday.

"The Ukrainian units that are there, they are there forever. They have two options: to surrender or die," Basurin said.

On Sunday, Zelenskyy said the latest fighting in Severodonetsk was "very fierce", adding that Russia was deploying undertrained troops and using its young men as "cannon fodder".