NEW YORK — The Justice Department will appeal a federal judge's ruling blocking its intervention on President Trump's behalf in a defamation lawsuit brought by an author who accused Trump of sexually assaulting her in the 1990s.

Lawyers for the department’s Civil Division filed a one-sentence notice of appeal on Wednesday afternoon indicating their intention to continue to try to represent Trump in the case brought by E. Jean Carroll.

In U.S. District Judge Lewis A. Kaplan’s 59-page ruling issued a month ago, he said Trump was not an “employee” under the federal law that Justice Department lawyers referenced to justify their entry into the case. The judge also decided that Trump’s comments denying the accusation did not amount to White House official business.

Since then, Kaplan has ordered the law firm of Marc Kasowitz, which has long represented Trump in personal matters, to step in again on Trump’s behalf.

If successful in getting back into the case, the Justice Department could argue that the lawsuit should be voided under the theory of “sovereign immunity,” which prevents lawsuits against the government from going forward.

Carroll’s lawyer Roberta Kaplan said she is “not at all surprised” that the Justice Department attorneys are still fighting “at the request of the White House.”

“From the very start of this case, Donald Trump’s number one goal has been to avoid discovery and cause delay,” Kaplan said in a statement, adding that it “remains to be seen” whether President-elect Biden’s pick for attorney general will support the effort.

Kaplan said she expects the U.S. Court of Appeals for the 2nd Circuit to “affirm [Judge Kaplan’s] comprehensive and well-reasoned opinion.”

In her 2019 memoir, Carroll, who at the time of publication was an advice columnist for Elle magazine, accused Trump of sexually assaulting her inside a dressing room at Bergdorf Goodman in Manhattan. In response, Trump called her a liar and suggested that her claim could not be true because he was not attracted to her.

Carroll sued the president for defamation but it was months before the Justice Department moved to intervene. That came at a point in the proceedings when it became clear that Trump would soon have to be deposed and provide a DNA sample to be compared to a stain of genetic material on the dress Carroll said she wore the day of the encounter.

Those steps in the discovery process have not yet taken place.

The action by Justice Department officials transferred the case from state court in New York to the U.S. District Court in Manhattan.