Reznikov, appointed three months before Moscow's invasion, has led Kyiv's negotiations to equip its forces with modern weaponry from allies.

His removal -- announced in a video late in the evening -- comes in the midst of Kyiv's counteroffensive and during Ukraine's general push against corruption in response EU requests.

It also paves the way for a major change in Ukraine's defence circles.

"Oleksiy Reznikov has been through more than 550 days of full-scale war," Zelensky said in his daily evening address.

"I believe that the ministry needs new approaches and other formats of interaction with both the military and society at large."

He nominated Rustem Umerov, a Crimean Tatar who has been head of the State Property Fund since last year, to replace Reznikov.

"Now Rustem Umerov should be the head of the (defence) ministry," Zelensky said in his evening address. "I expect parliament to support this candidate."

Reznikov, a 57-year-old lawyer with little military experience, has become one of the best-known faces of Kyiv's war effort.

During the Russian invasion, Ukraine's defence ministry has been rocked by some corruption scandals.

In January, Reznikov kept his job but his deputy was forced to resign after the defence ministry was accused of signing food contracts at prices two to three times higher than current rates for basic foodstuffs.