The former national security adviser to Mike Pence and retired lieutenant general quickly fell out of favor with White House officials who saw him as too sympathetic to Ukraine.

Kellogg has served as Trump’s special envoy to Ukraine since early 2025, in a role that did not initially require full Senate confirmation. Reuters reported that Kellogg’s decision to exit stemmed in part from the temporary nature of his role, which would have necessitated a confirmation process to extend his service beyond a 360-day tenure.

New York City Mayor-elect Zohran Mamdani told reporters his meeting with President Trump was productive, with the two leaders sharing a love of their shared hometown.