Trump sued for defamation by former Apprentice Summer Zervos

A former Apprentice contestant who accuses US President-elect Donald Trump of sexual assault has filed a defamation lawsuit against him.

Summer Zervos, who alleges Mr Trump forced himself on her in 2007, said he lied to the nation about his behaviour.

The lawsuit, which Ms Zervos announced at a news conference, alleges Mr Trump is a "liar and misogynist" who "debased and denigrated" her.

The news came just three days before Mr Trump is sworn in as president.

"Since Mr Trump has not issued a retraction, as I requested, he has therefore left me with no alternative but to sue him in order to vindicate my reputation," Ms Zervos said at a news conference.

She was joined by her lawyer, Gloria Allred, who said the plaintiff's allegations had passed a lie detector test.

Ms Zervos is one of several women who came forward to accuse Mr Trump of sexual assault in the weeks leading up to the presidential election.

The 41-year-old former reality show contestant said Mr Trump sexually assaulted her during a meeting to discuss job opportunities at a Beverly Hills, Los Angeles hotel.

She said he "began thrusting his genitals" as she fended off his advances.

The president-elect has dismissed the claims as "false and ridiculous" and vowed to sue the accusers for their allegations.

Mr Trump has not filed a lawsuit against any of the women.

Ms Zervos' lawsuit alleges that the president-elect defamed her by denying her account and accusing her and other women of fabricating sexual assault claims.

She asked Mr Trump to retract his words late last year, but he declined to do so.

Ms Allred said Mr Trump "knowingly, intentionally, and maliciously threw each of these women under the bus," and that repeatedly calling them "liars" in public caused distress.

Ms Zervos added that she would be willing to rescind the lawsuit if the president-elect retracts the statements he made and acknowledges his behaviour towards her.

The incoming 45th president faced a series of sexual assault allegations after the October release of a 2005 videotape in which he is caught making lewd comments about groping women.

The video prompted several women, including Ms Zervos, to come forward.