Ukrainian Foreign Minister Dmytro Kuleba resigned on Wednesday, the highest-profile casualty so far of a major government reshuffle ordered by President Volodymyr Zelenskyy at a crucial juncture in the 30-month war against Russia.

After Zelenskyy, 43-year-old Kuleba was the best-known face of Ukraine overseas, meeting leaders around the world and lobbying for military and political support in fluent English.

More resignations and appointments are expected over the coming days after five ministers stepped down on Tuesday, in what a senior Zelenskyy ally cast as the start of a government "reset" ahead of the cold autumn and winter seasons.