Ukrainian President Volodymyr Zelenskyy on Sunday demanded rapid changes in the operations of Ukraine's military and announced the dismissal of the commander of the military's medical forces.

Zelenskyy's move was announced as he met Defense Minister Rustem Umerov, and coincided with debate over the conduct of the 20-month-old war against Russia, with questions over how quickly a counteroffensive in the east and south is proceeding.

"In today's meeting with Defense Minister Umerov, priorities were set," Zelenskyy said in his nightly video address. "There is little time left to wait for results. Quick action is needed for forthcoming changes."