Ukrainian forces struggled to hold their ground in bloody street-to-street fighting in the eastern frontline city of Sievierodonetsk as President Volodymyr Zelenskiy said the situation was difficult, also pledging to retake Russia's gains.

The days-long battle for the industrial city has emerged as pivotal, with Russia focusing its offensive might in the hope of achieving one of its stated aims - to fully capture surrounding Luhansk province on behalf of Russian-speaking...