Ukrainian forces have launched a major new attack in Russia's western Kursk region, Russian military bloggers reported on Sunday.
Ukrainian troops broke across the border in a surprise incursion on Aug. 6, and for the past five months have resisted Russian attempts to expel them.
Reports from the Russian bloggers, who support Moscow's war in Ukraine but have often reported critically on failings and setbacks, indicated that the latest Ukrainian assault had put Russian forces on the defensive.
"Despite strong pressure from the enemy, our units are heroically holding the line," the Operativnye Svodki (Operational Reports) channel said.
It said artillery and small-arms battles were taking place, and Ukraine was using Western-armored vehicles to bring in large numbers of infantry.
The reports, which Reuters could not independently verify, said fighting was concentrated near the town of Bolshoye Soldatskoye.
But one influential blogger, Yuri Podolyak, said this was most likely a Ukrainian distraction manoeuvre, possibly to prepare a strike on Glushkovo, further west. He recommended civilians there and in another town, Korenevo, to evacuate.
Ukrainian and Western assessments say that some 11,000 troops from Russia's ally North Korea have been deployed in the Kursk region to support Moscow's forces. Russia has neither confirmed nor denied their presence.
Ukrainian President Volodymyr Zelenskiy said on Saturday that Russian and North Korean forces had suffered heavy losses.
"In battles yesterday and today near just one village, Makhnovka, in Kursk region, the Russian army lost up to a battalion of North Korean infantry soldiers and Russian paratroops," Zelenskiy said. "This is significant."
The president provided no specific details. A battalion can vary in size but is generally made up of several hundred troops.
Russian President Vladimir Putin said in response to a question at his marathon annual phone-in last month that Russia would definitely drive Ukrainian forces out of Kursk but declined to set a date for when this would happen.
Russia's defense ministry did not mention Kursk in its latest battlefield update on Sunday.
BARGAINING CHIP
Ukraine's unexpected success in biting off a slice of Russian territory and holding on to it since last August could provide it with an important bargaining chip as both sides gear up for possible peace talks this year.
Both have been striving to improve their battlefield positions before US President-elect Donald Trump is sworn in on Jan. 20. Trump has repeatedly said he will bring a quick end to the war, but without saying how.
By committing some of its most effective units to the Kursk offensive, Ukraine has, however, weakened the defense of its own eastern regions where Russian forces have advanced since August at their most rapid pace since 2022.
The Ukrainian military said on Saturday that the "hottest" front was near Pokrovsk, an important road and rail hub towards which Russia has been pressing for months.
On Sunday, Ukraine's air defenses shot down 61 out of 103 drones launched by Russia in an overnight attack, the air force said. Russia said it had destroyed five Ukrainian drones over Russian territory.
