US President Donald Trump will sign an executive order on Friday to rename the Department of Defence the "Department of War," White House spokesperson Karoline Leavitt confirmed.

The order, first reported by Fox News, restores the historic title that was used until 1949, when the National Security Act of 1947 reorganised the military establishment under its current name.

According to the order, the "Department of War" will serve as a secondary title, while Secretary of Defence Pete Hegseth will formally assume the additional title of "Secretary of War."

The directive also instructs Hegseth to propose legislative and executive measures to make the change permanent.

It calls for updates across Pentagon signage and websites, including renaming the public affairs briefing room the "Pentagon War Annex," a White House official told Fox.

"Everybody likes that we had an unbelievable history of victory when it was the Department of War," Trump told reporters on August 25.

Hegseth welcomed the move, saying it reflected a broader cultural shift.

"We’re not just defence, we’re offence," he said.

Aggressive posture

The Department of War was created in 1789, the same year the US Constitution took effect, and managed the nation’s military through World War II.

Following World War II, Congress replaced it with the Department of Defense to reflect a Cold War-era emphasis on containment and alliances.

The Trump administration has argued that reviving the title underscores military strength and restores clarity of purpose.

Critics, however, warn that it signals a rhetorical shift toward an aggressive posture and could undermine US diplomatic messaging.

Trump said he expected Congress to back legislation if needed to formalise the rebrand.

"We’re just going to do it. I’m sure Congress will go along if we need that," he said.