Thousands of troops fighting in Russia have been surrounded in what's been dubbed a major blow to the Ukrainian war effort.

LONDON/KYIV >> Thousands of Ukrainian troops who stormed into Russia’s Kursk region last summer in a shock incursion are nearly surrounded by Russian forces there, in a major blow to Kyiv which hoped to use its presence there as leverage over Moscow in any peace talks.

Tens of thousands of Ukrainian troops who smashed into Russia last summer and took control of a swathe of territory there are nearly encircled by Russian forces and cut off from their main supply lines,