The deputy head of Ukraine’s presidential office quit Tuesday, after Ukrainian President Volodymyr Zelensky pledged to launch a staff shake-up amid high-level corruption allegations during the war with Russia.

Kyrylo Tymoshenko asked to be relieved of his duties, according to an online copy of a decree signed by Zelensky and Tymoshenko’s own social media posts. Neither gave a reason for the resignation. Deputy Defense Minister Viacheslav Shapovalov also resigned, local media reported, alleging his departure was linked to a scandal involving the purchase of food for the Ukrainian Armed Forces.