Caught unaware by Ukraine’s military incursion into Russia, the Biden administration is debating whether to help Kyiv’s forces hold the sliver of territory they now occupy.

Russia said on Thursday its troops had beaten back an attempt by a Ukrainian force to infiltrate its border in a different region to Kyiv's incursion onto Russian territory, while Ukrainian drones struck near an air base in southern Russia.

The Ukrainians must defend a critical front in their country’s east, including the city of Pokrovsk, while trying to press forward in western Russia.