President Donald Trump has accused Democrats of using a “con game” to try scuttling Brett Kavanaugh’s Supreme Court nomination.

He also disparaged the account of the second woman accusing Kavanaugh of sexual misconduct, saying she herself conceded she was “totally inebriated and all messed up”.

Trump’s remarks came as Republicans worked to shore up support for the beleaguered Kavanaugh, whose march toward Senate confirmation has been rocked by allegations of decades-old sexual improprieties from two women.

On Friday, Trump had mocked claims by Kavanaugh’s chief accuser of a sexual assault at a 1980s’ high school party, tweeting that she would have reported the incident to police if it was “as bad as she says”.

While other Republicans have sought to undermine the women’s accounts, Trump has gone further.

Most Republican politicians have been less acidic in challenging the women’s credibility, mindful of competitive November elections in which many female voters are already expected to abandon Republican candidates because of hostility toward Trump.

In remarks to reporters at the United Nations, Trump took aim at Deborah Ramirez, Kavanaugh’s second accuser.

Brett Kavanaugh during a Fox News interview with Martha MacCallum (Jacquelyn Martin/AP)

She told The New Yorker magazine that at a party both attended as Yale freshmen in the 1980s, a drunken Kavanaugh placed his penis in front of her and caused her to involuntarily touch it.

She has said she was inebriated as well and has admitted to holes in her memory of some details.

“She said, well it might not be him, and there were gaps, and she was totally inebriated and all messed up,” Trump told reporters.

“She doesn’t know it was him but it might have been him and ‘Oh gee let’s not make him a Supreme Court judge because of that’.

“This is a con game being played by the Democrats.”

Trump called Kavanaugh “just a wonderful human being” and suggested that Democrats were sceptical of Ramirez, saying: “They don’t believe it themselves.”

He said rejecting Kavanaugh would be “a horrible insult” and “a very dangerous game” for the US.

Trump spoke two days before the Senate Judiciary Committee plans a pivotal, election-season hearing at which both Kavanaugh and his chief accuser, Christine Blasey Ford, are due to testify separately.

That session, certain to be must-watch television for the nation, looms as a do-or-die wild card for Kavanaugh in which a split-second facial expression, a tear or a choice of words by either witness could prove decisive.

Ford has said Kavanaugh tried removing her clothes and covered her mouth to prevent screams after he pinned her on a bed during a high school party.

Kavanaugh, 53, a judge on the District of Columbia Circuit Court of Appeals, has denied both women’s stories.

In a Fox News interview Monday night, Kavanaugh said he would not let “false accusations drive me out of this process”.

Agreeing to a television interview was an extraordinary step for a high court nominee.

Kavanaugh said on the conservative-friendly Fox News Channel that he was not questioning that Ford, his initial accuser, may have been sexually assaulted in her life.

But he added: “What I know is I’ve never sexually assaulted anyone,” a remarkable assertion for a nominee to the nation’s highest court.