Russia said Wednesday for the first time that some Ukrainian troops had established positions on the Moscow-held side of the Dnipro River, the vast waterway that splits the frontline in southern Ukraine.A sustained Ukrainian breakthrough across the river would mark a significant tactical success for Kyiv, whose wider counteroffensive has so far failed to turn the tide of the 21-month war."Small groups" of Ukrainian soldiers were stretched along the eastern bank of the Dnipro river, and had been "blocked" in the tiny village of Krynky, the Moscow-installed head of Ukraine's Kherson region, Vladimir Saldo, said in a post on Telegram.But he insisted they were facing a "fiery hell" from Russian artillery, rockets and drones, and were suffering heavy losses.Russian and Ukrainian forces have been entrenched on opposite sides of the Dnipro River since Moscow withdrew from the western part of the Kherson region last November.That was the last major territorial change in the conflict, with both sides having since failed to make any significant progress despite staging multiple offensives.Russia's Saldo said Wednesday that "about one and a half enemy companies, mostly in small groups," were currently on the Russian-held side.According to Russia's TASS news agency, a company in the Russian military system consists of 45-360 soldiers."Our additional forces have now been deployed.

The enemy is blocked in Krynky.

A fiery hell has been arranged for them: bombs, rockets, heavy flamethrower systems, artillery shells and drones are flying at them," Saldo said.His comments were the first admission by a senior Russian official that Ukraine had managed to secure some positions on the Russian-controlled side of the river.AFP was not able to verify his reports and the scale of Ukraine's crossing was unclear.Since mid-October, Russian military bloggers close to the armed forces have been reporting that small groups of Ukrainian troops were successfully crossing the river.The Kremlin earlier this week refused to comment on those reports, deferring questions to the Defense Ministry.The ministry has not spoken about it either, but said separately that it had captured a small group of Ukrainian soldiers "trying to land on the left bank."Both Kyiv and Moscow regularly claim to have killed high numbers of "enemy" soldiers, though neither side comments on their own losses.Despite a relatively static frontline, both Kyiv and the Kremlin have denied the conflict has ground to a stalemate.