Ukraine said Monday it had lost control of a village adjacent to the eastern industrial city of Severodonetsk, the centre of weeks of fierce fighting with invading Russian troops.

"Unfortunately, we do not control Metyolkine anymore. And the enemy continues to build up its reserves," the Lugansk regional governor Sergiy Gaiday said in a statement on social media.

Russia's capture of the hamlet with a pre-war population of around 1,000 people, is the latest  around Severodonetsk, where Moscow's army has met tough Ukrainian resistance.

Russian troops have slowly advanced in the eastern Donbas region where they focused their military efforts after being pushed out from areas around the capital at the start of their invasion in February.

Gaiday said that the Azot chemical plant in Severodonetsk, where  hundreds of civilians are said to be sheltering, was being shelled by Russian forces "constantly".

The head of the city administration, Oleksandr Stryuk meanwhile told Ukrainian television Monday that Moscow's army controls most of the city's residential areas.

"If we talk about the whole city, still more than a third is controlled by our armed forces. Russians control the rest," he said.

"There are street battles around the clock," he added, saying Ukrainian troops were being shelled routinely. 

"The enemy is throwing more and more manpower into the offensive, to storm the city and push out our soldiers," Stryuk said.

Evacuations from Severodonetsk have not been possible for days, after a last bridge across the river connecting it to Lysychansk was blown up.