Authorities in Ukraine's Sumy region bordering Russia ordered the mandatory evacuation of 11 villages because of bombardments, as Kyiv feared a Russian offensive there.
"This decision takes into account the constant threat to civilian lives because of the bombardments of border communities," Sumy's administration said.
Russia's defence ministry said its forces had taken another Sumy village, Vodolagy, known as Vodolahy in Ukrainian.
Russia in recent weeks has claimed to have taken several villages in the northeastern region, and Ukrainian President Volodymyr Zelensky said this week that Moscow was massing more than 50,000 soldiers nearby in a sign of a possible offensive.
A spokesman for Ukraine's border guard service, Andriy Demchenko, on Thursday, said that Russia was poised to "attempt an attack" on Sumy.
He said the Russian troop build-up began when Moscow's forces fought Ukrainian soldiers who last year had entered the Russian side of the border, in the Kursk region.
Russia has recently retaken control of virtually all of Kursk.
Currently, Russia - which launched its all-out invasion in February 2022 - controls around 20% of Ukrainian territory. The ongoing conflict has killed tens of thousands of soldiers and civilians on both sides.
Washington has been leading diplomatic efforts to try to bring about a ceasefire, but Kyiv and Moscow accuse each other of not wanting peace.
The Kremlin has proposed further negotiations in Istanbul on Monday after a 16 May round of talks that yielded little beyond a large prisoner-of-war exchange.
Kyiv has not yet said whether it will attend the Istanbul meeting and is demanding that Moscow drop its opposition to an immediate truce.
