WASHINGTON, Sept. 8 (Xinhua) -- The U.S. Justice Department on Tuesday moved to defend President Donald Trump in a defamation lawsuit brought by E. Jean Carroll, a woman who has accused Trump of sexual assault in the mid-1990s.

Carroll, an advice columnist who wrote for Elle Magazine for years, filed a defamation suit in November after the president denied her allegation that he sexually assaulted her in a dressing room at department store Bergdorf Goodman in Manhattan in the 1990s. Trump has called the allegation "totally false."

Facing criticism that the Justice Department has acted in the president's personal interests at taxpayer expense, the federal law enforcement agency argued in court papers on Tuesday that Trump's denials came while he was in office.

"Because President Trump was acting within the scope of his office or employment at the time of the incident out of which the plaintiff's claim arose, the United States will file a motion to substitute itself for President Trump in this action for any claim for which the FTCA (Federal Tort Claims Act) provides the exclusive remedy," the Justice Department's court filing stated.

Local media said it is unusual for the Justice Department to intervene in a private legal matter on behalf of a sitting president.