President Volodymyr Zelenskyy on Friday appointed Ukraine’s military intelligence chief as chief of staff, a move that comes as Washington ramps up diplomacy aimed at ending Russia’s nearly four-year invasion.

In announcing the appointment of Gen. Kyrylo Budanov, Zelenskyy said Ukraine needs to focus on security issues, developing its defense and security forces, and peace talks – areas that are overseen by the office of the president.

Zelenskyy had dismissed his previous chief of staff, Andrii Yermak, after anti-corruption officials began investigating alleged graft in the energy sector.

Budanov, 39, is one of the country’s most recognizable and popular wartime figures. He has led Ukraine’s military intelligence agency, known by its acronym GUR, since 2020.

A career military intelligence officer, he rose through the defense establishment after Russia’s illegal annexation of Crimea in 2014. He also took part in special operations and intelligence missions linked to the fighting with Moscow-backed separatist forces in eastern Ukraine before the full-scale invasion of February 2022. He reportedly was wounded during one such operation.