Ukrainian forces have reportedly recaptured nearly two square kilometers of territory in the northeastern Kharkiv region.
The 3rd Separate Assault Brigade said it was behind the counteroffensive, but did not provide any details on when it was launched or what area had been recaptured.
As such, it's difficult to predict whether it will have further impact on the battlefield.
However, the Ukrainian military did say it had taken control of an area that was held by a Russian battalion.
Brigade Commander Andrii Biletskyi said the ratio of forces on the battlefield was 2:5:1 in Moscow's favour.
Sky News is unable to verify this battlefield report.
Russia had launched a large offensive in the region in the spring which brought initial gains, but the operation later stalled.
Ukraine's forces have gained momentum and altered the battlefield this month, launching a shock offensive into Russia's Kursk region.
They have also intensified a drone war against Russia's military and fuel targets, including destroying a ferry taking fuel supplies to Crimea.
Ukraine is now hoping the regained momentum could strengthen Kyiv's hand on the diplomatic front.
