Army Secretary Dan Driscoll has resigned after months of reported tension with Defense Secretary Pete Hegseth, leaving the Army without a Senate-confirmed civilian or military leader. President Donald Trump accepted Driscoll’s resignation Monday evening, according to a U.S. official, and the White House thanked Driscoll for his service, calling him “highly effective.”

Driscoll’s departure follows ongoing disagreements with Hegseth about the direction of the Army and the removal of several senior officers. According to reporting from the Wall Street Journal, Driscoll is expected to officially leave the Pentagon in the coming days.

Hegseth, a former Army National Guard officer, has been consolidating power at the Pentagon, pushing out or stalling the promotions of dozens of top Army officials. These actions have caused concern among both Democratic and Republican lawmakers. Senator Mike Rounds said he was “disappointed” by Driscoll’s exit, while Representative Don Bacon called for more transparency and respect in leadership changes.

Driscoll, who previously pushed for Army modernization and better living conditions for soldiers, earned bipartisan praise for his work. However, his bipartisan relationships reportedly did not help him maintain influence against Hegseth’s assertive approach.

With Driscoll gone, General Christopher LaNeve, a close adviser to Hegseth, has been appointed as acting Army chief of staff, but his nomination has faced Senate objections. Hegseth is also considering his senior adviser, Sean Parnell, as Driscoll’s successor, though Parnell’s confirmation could be challenging due to past controversies.

Some lawmakers, like Representative Steve Womack, praised Driscoll as “a transformative leader,” while others questioned Hegseth's management style and the rapid changes at the Pentagon. The Army now faces uncertainty as it waits for new leadership and possible Senate confirmation hearings.