Vladislav Shapsha, governor of the Kaluga region, which borders the Moscow region to its northeast, said a non-residential building in the region was on fire as result of Ukraine's drone attack. Reuters could not independently verify the reports. There was no immediate comment from Ukraine.

The surge in fighting occurs as President-elect Donald Trump pledges to end the conflict.

Russia launched a new barrage of drones in an overnight attack on Ukraine on Friday, killing one civilian and wounding more than 30 people in the centre, south, and northeast of the country, Ukrainian officials said.

Experts warn that Russia may be trying to deplete Ukraine's air defences in preparation for an attack on its energy system over the winter. Ukraine has also increased its use of long-range drones in recent weeks,

Russia and Ukraine have carried out their biggest drone attacks against each other since the start of the war. Russia's defence ministry also said it intercepted 70 Ukrainian drones over six regions, including some approaching Moscow which forced flights to be diverted from three of the capital's major airports.

The Washington Post reported that Trump had had a phone call on Thursday with the Russian strongman in which he told Putin not to inflame the attritional war.

Ukrainian UAVs attacked ammunition depots belonging to the 1060th Logistics Centre (formerly the 120th Arsenal of the Main Missile and Artillery Directorate) in Russia's Bryansk Oblast on the night of 9-10 November.

During the night from Saturday to Sunday, Ukrainian forces carried out a drone attack on a Russian weapons storage facility in the Bryansk region, which borders Ukraine. The attack resulted in eight explosions and a large fire.