Ukraine has lost over 40% of the territory in Russia's Kursk region that it rapidly seized in a surprise incursion in August as Russian forces have mounted waves of counter-assaults, a senior Ukrainian military source said.

Ukraine has lost more than 40 per cent of the territory in Russia’s Kursk region that it seized in August, a senior Ukrainian military source said. Russia had deployed 59,000 troops to the region since the surprise invasion by Kyiv’s forces,