The New Yorker's report says at least four Democratic senators have received details of the allegation. The accusations from Christine Blasey Ford, denied vehemently by Kavanaugh, threaten to slow his Senate confirmation vote, with Democrats saying the FBI should investigate the charges, a demand that is not gaining traction among Republicans. In addition, the New Yorker claims, some Republicans in the Senate were also informed about the new accusations.
Ford, a 51-year-old psychology professor, has accused Kavanaugh of sexually assaulting her when they were both teenagers.
Lawyers for Ford and bipartisan representatives of the committee came to the temporary agreement after a short phone call, said one of the people, who was not authorized to speak publicly and requested anonymity.
Ford identified one other witness, Mark Judge, in a September 16 Washington Post article where she first told her story.
The magazine reported that after "six days of carefully assessing her memories and consulting with her attorney, Ramirez said that she felt confident enough of her recollections" to recall the incident.
Senate Judiciary Committee Chairman Chuck Grassley, R-Iowa, wrangled with Ford's lawyers for the past week over the exact terms of her appearance.
Kavanaugh, who had unequivocally denied Ford's allegations, immediately denied the new accusations as well, and the White House gave no signal that President Trump was inclined to withdraw Kavanaugh's nomination.
Blasey Ford's lead attorney, Debra Katz, at the same time heads a leftist advocacy group funded by liberal megadonor George Soros, who also is funding Demand Justice, which has raised $5 million to sink Trump's high-court picks.
The staff wrote in one email that Grassley asked them to convey that "the Committee determines which witnesses to call, how many witnesses to call, in what order to call them, and who will question them".
The allegation is the latest twist in Mr Kavanaugh's already heated confirmation battle.
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Defections among Republicans would probably block his path to the Supreme Court.
The White House is approaching Ford's potential testimony with trepidation, nervous that an emotional performance might not just damage Kavanaugh's chances but could further energize female voters to turn out against Republicans in November against the backdrop of the #MeToo movement.
"I would think an FBI investigation would be warranted", she told The New Yorker.
"Judge Kavanaugh is an outstanding person, and I am with him all the way".
"Various senators have been dismissive of her (Ford's) account and should have to shoulder their responsibility to ask her questions", Ford's lawyers say.
Several of Kavanaugh's Yale classmates say he would never have done such a thing.
But details are still being worked out and, given the events of the past week, there is no guarantee Ford will actually take the oath and submit to what are certain to be intensely probing questions about her credibility.
As he builds a case for his innocence, Mr Kavanaugh plans to turn over to the committee calendars from the summer of 1982.
The only crimes Brett Kavanaugh is guilty of is being a white male who is religious, conservative and pro-life.
"We are aware of significant evidence of multiple house parties in the Washington, D.C. area during the early 1980s, during which Brett Kavanaugh, Mark Judge and others would participate in the targeting of women with alcohol/drugs to allow a "train" of men to subsequently gang rape them".
"Congress failed the test in 1991 with Anita Hill", Senator Patty Murray, Democrat of Washington state, said on NBC's "Meet the Press" Sunday.