Ukrainian President Volodymyr Zelenskyy says he has decided to replace his defense minister, setting the stage for the biggest shake-up of Ukraine's defense establishment since Russia launched its full-scale invasion in February 2022.

In his nightly video address to the nation, Zelenskyy said on Sunday that he would dismiss Defense Minister Oleksii Reznikov and would ask parliament this week to replace him with Rustem Umerov, head of the country's main privatization fund.

Reznikov, defense minister since November 2021, has helped secure billions of dollars of Western military aid to help the war effort, but has been dogged by graft allegations surrounding his ministry that he has described as smears.