KYIV: Ukrainian forces are in control of the entire northeast region of Sumy along the border with Russia, its governor said Friday, warning residents against returning while it was being cleared of mines.

"The area is free of orcs," Sumy regional governor Dmytro Zhyvytsky said on social media, referring to invading Russian troops.

"The region is not safe. There are many areas that have been mined and are still not cleared," he said.

Russian forces have recently withdrawn from territory in the north and around the capital Kyiv after announcing a push to capture the eastern Donetsk and Lugansk regions, which are south of Sumy.

Shift in momentum: Ukrainian forces advance east of Kyiv as Russians fall back

The eastern regions have been partially controlled by pro-Russia separatists since 2014, when nationwide street demonstrations led to the ouster of a Kremlin-friendly president and sparked a conflict between Kyiv's army and the rebels.

Zhyvytsky has said earlier that Russian troops were withdrawing from the area after Moscow's announcement to shift its military aims to the Donbas.

Despite Friday's announcement that Ukraine forces were in control of Sumy, he said that the proliferation of unexploded ordnance meant the area was still unsafe for residents.

"If you hear explosions -- and there have been many in recent days -- it's emergency workers and technicians specialised in explosives. They are defusing the ammunition left by the Russian military on our land."

"Do not drive on the sides of roads and do not use forest roads. Do not approach destroyed equipment or orc sites! It's not time to clean up yet. First -- demining" he added.

Sumy, a city with a pre-war population of around 250,000 people and administrative centre of the region was besieged early in Russia's invasion.