At least two people have been killed and another 17 injured in the biggest Russian drone attack on Ukraine's second-largest city of Kharkiv, the mayor says. Ihor Terekhov says that overnight Russia launched 48 drones, as well as two missiles and four gliding bombs.

Russia will take years to replace nuclear-capable bomber planes that were hit in Ukrainian drone strikes last weekend, according to Western military aviation experts, straining a modernisation programme that is already delayed.