Ukrainian President Volodymyr Zelenskyy says his country survived the winter due to government efforts to ensure energy and heat amid Russian strikes on infrastructure.

In a video message on Wednesday, Zelenskyy said, "This winter is over. It was very difficult, and every Ukrainian without exaggeration felt this difficulty. But we still managed to provide Ukraine with energy and heat."

He said he held a meeting on the stability of the country's energy infrastructure and that the government has already started preparing for the next season.

Russia is intensifying its attacks to take full control of Ukraine's eastern region of Donbas.

Ukraine has announced plans to launch a major spring counteroffensive to retake territory seized by Russia.

In an interview with German media published on Sunday, the deputy head of Ukraine's military intelligence, Vadym Skibitsky, said an aim of the counteroffensive is to "drive a wedge into the Russian front in the south between Crimea and mainland Russia."