(L-R) Rachel Crooks, Jessica Leeds, and Samantha Holvey speak during the press conference held by women accusing Trump of sexual harassment in NYC on December 11, 2017 in New York City.

Three women who have accused President Donald Trump of sexually harassing or assaulting them before he came to the White House demanded a congressional investigation Monday, following a week in which lawmakers from both parties were forced into resignation amid harassment allegations.

"People are being held accountable, except for our president," said Jessica Leeds, who said Trump tried to force himself on her, including reaching under her skirt, during a plane ride more than 30 years ago. Yet "his staff made a big point of calling us all liars," she said. More than a dozen women accused Trump of sexual misconduct during his presidential campaign last year.

Leeds, Samantha Holvey and Rachel Crooks said the national discussion over sex harassment has felled powerful men across major industries including entertainment and on Capitol Hill. Meantime Trump "has escaped his past unscathed" and "our stories seem to fall on deaf ears," said Crooks.

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Crooks says Trump held her hand and kissed her on the mouth when she was working as a receptionist at Trump Tower in Manhattan.

The women also appeared in an earlier interview with Megyn Kelly, prompting the White House to issue a statement saying Trump has denied all of the accusations and that the women were making "false claims."

The "timing and absurdity of these false claims speaks volumes," the White House said in a statement that bore no one's name, reiterating that the American people "voiced their judgement" by electing the president. Trump won the electoral vote while receiving about 2.9 million fewer votes than Democrat Hillary Clinton.

The news conference came the Monday after Sen. Al Franken, D-Minn., gave a pointed speech on the Senate floor announcing his resignation and taking a parting shot at Trump.