By Doina Chiacu

WASHINGTON (Reuters) - U.S. President Donald Trump rejected Democrats' calls for impeaching Supreme Court Justice Brett Kavanaugh on Sunday after a new report involving sexual misconduct allegations, encouraging Kavanaugh to sue for libel and suggesting the Justice Department could "rescue" him.

Some Democratic presidential candidates called for Kavanaugh's impeachment, saying he lied under oath, after a New York Times report on Saturday disclosed new information about sexual misconduct allegations against him.

The Times essay, drawn from an upcoming book written by the newspaper's reporters, said it was able to corroborate an allegation by former classmate Deborah Ramirez that Kavanaugh exposed his penis to her during a drunken party at a Yale University when they were undergraduates.

"Brett Kavanaugh should start suing people for libel, or the Justice Department should come to his rescue," Trump wrote on Twitter.

It was unclear what action the Republican president was advocating the Justice Department take.

The Times article said at least seven people, including Ramirez' mother, had heard about the incident long before Kavanaugh became a judge. Kavanaugh denied Ramirez' accusations during his acrimonious Senate confirmation hearing last fall.

The Times piece also disclosed a previously unreported account that echoes Ramirez' story. Former Yale classmate Max Stier describes Kavanaugh pushing his private parts into the hand of a female student at a party. The report said the classmate notified U.S. senators and the FBI about the incident, but the FBI did not investigate. The FBI declined to comment on the report.

Kavanaugh did not comment to the Times on the allegations. The Supreme Court press officers did not immediately return a request for comment.

Kavanaugh, a conservative appointed by Trump, was confirmed by the U.S. Senate in October after he denied accusations of sexual assault from three women. The Senate confirmed his appointment to the high court by 50-48 vote, one of the tightest margins ever for a justice.

Some of the Democrats running to replace Trump in 2020 called for Kavanaugh's impeachment in Twitter posts on Sunday.

"The revelations today confirm what we already knew: During his hearing, Kavanaugh faced credible accusations and likely lied to Congress," U.S. Senator Bernie Sanders said.

"I sat through those hearings. Brett Kavanaugh lied to the U.S. Senate and most importantly to the American people," wrote Senator Kamala Harris, a Judiciary Committee member. "He must be impeached."

"Confirmation is not exoneration, and these newest revelations are disturbing. Like the man who appointed him, Kavanaugh should be impeached," Senator Elizabeth Warren said in another Twitter post.

Former Congressman Beto O'Rourke joined the chorus on Sunday, as did former U.S. Housing Secretary Julian Castro, who launched the calls for Kavanaugh's impeachment on Saturday.

Senator Amy Klobuchar posted a picture of the woman who testified to the Senate about her allegations against Kavanaugh, Christine Blasey Ford, with the caption, "Let us never forget what courage looks like."

Trump did not mention the Times article but blamed "radical left Democrats" and the "LameStream Media" for going after Kavanaugh. In a series of Twitter posts, he accused Democrats of threatening impeachment to influence Kavanaugh's opinions on court cases.

"They want to scare him into turning Liberal!" he wrote.

(Reporting by Doina Chiacu; Editing by Lisa Shumaker)