Russia bombed a TV tower in Ukraine's capital on Tuesday and rained rockets on the city of Kharkiv as Moscow intensified its bombardment of Ukrainian urban areas in a shift of tactics after its six-day invasion stalled.

A US official said a miles-long armoured column bearing down on the capital Kyiv had not made any advances in the past 24 hours, frozen in place by logistics problems, short on fuel and food, and perhaps pausing to reassess tactics.

Russia's defence ministry urged...