Fewer attacks were reported in Ukraine and Russia overnight as a unilateral ceasefire announced by Ukrainian President Volodymyr Zelensky took effect on Wednesday.
The Russian Defence Ministry reported 53 Ukrainian drones were intercepted over its territory and the annexed Crimean Peninsula, Russian news agencies reported.
It was unclear whether the drones were shot down before the start of Zelensky's ceasefire, which began at midnight on Wednesday (2100 GMT Tuesday.)
Russia's own temporary ceasefire is set to come into force on Friday and Saturday, as Moscow celebrates Victory Day on May 9, commemorating the Soviet Union's defeat of Nazi Germany.
However, Russian airstrikes also appeared to ease overnight after dozens were killed in Ukraine earlier on Tuesday.
The Ukrainian Air Force said drones approached the eastern city of Kharkiv after the Ukrainian ceasefire took effect.
It said Russia launched attacks with three missiles and 108 drones since 6 pm on Tuesday, adding that 89 drones were intercepted.
Nevertheless, one woman was reported killed in a Russian drone strike on the north-eastern Sumy region.
Military governor Oleh Hryhorov wrote on Telegram that Russia struck a civilian car. The driver was taken to hospital with injuries, while a female passenger was killed.
The Sumy region borders Russia and has been severely affected by the fighting in the conflict, which has been ongoing for more than four years.
