"That’s a big one," Trump said after signing the decree, TASS reported.
He added that the new name was much more appropriate given the current state of the world.
The head of the US administration noted that the possibility of renaming the Pentagon had been discussed for several months.
Pentagon Chief Pete Hegseth, whom Trump called secretary of war, said that after the department had been renamed the Ministry of Defense in the middle of the 20th century, the United States did not win any major wars. According to Hegseth, the return of the old name will allow the department he heads to fight decisively and prevent endless conflicts.
The US Department of War existed from 1789 to 1947, when it was transformed into the national military department. In 1949, it was renamed the US Department of Defense.