The Ukrainian minister in charge of weapons production resigned on Tuesday in anticipation of another defense role and four other ministers stood down in a major government shake-up at a critical juncture in the war with Russia.

The resignations of Strategic Industries Minister Oleksandr Kamyshin, Deputy Prime Minister Olha Stefanishyna and the justice, environment and reintegration ministers leaves over a third of the cabinet vacant after sackings earlier this year.

Ukrainian President Volodymyr Zelenskyy and his political allies could move to fill the positions to create order before he travels this month to the United States, where he hopes to present a "victory plan" to U.S. President Joe Biden, a key ally.