Washington, Sep 30 (IANS): US President Donald Trump has ordered an FBI investigation into sexual misconduct allegations against his US Supreme Court nominee Brett Kavanaugh, throwing his confirmation into doubt.

A Senate committee voted on Friday to approve Kavanaugh's nomination to the top US court. But a Republican member only backed the move on the understanding that such an inquiry would occur, the US media reported.

As a result, a full Senate vote on Kavanaugh's confirmation has been delayed for up to a week. He has been accused of sexually assaulting Christine Blasey Ford, a professor of psychology in California, in 1980s.

"I've ordered the FBI to conduct a supplemental investigation to update Judge Kavanaugh's file," Trump said in a statement. "As the Senate has requested, this update must be limited in scope and completed in less than one week."

Trump's announcement followed a letter from the Senate judiciary panel seeking an expedited probe of the allegations pursuant to a bipartisan agreement to put off a vote on the nomination.

According to CNN, the developments mean that the full Senate will not vote early next week, as expected. Members voted on Friday night to formally open consideration of Kavanaugh's nomination, a procedural move allowing Senate Majority Leader Mitch McConnell to keep his options open.

The delay was the result of a last-minute change of heart by Arizona Senator Jeff Flake, whose move to force an investigation was quickly backed by several senators considered swing votes on Kavanaugh's confirmation.

Flake made the demand for the Federal Bureau of Investigation probe after a chaotic scene at a Senate Judiciary Committee meeting in which the panel advanced Kavanaugh by a 11-10 party line vote -- saying his vote was conditioned on a probe taking place, and that he would oppose Kavanaugh on the floor of the Senate unless his demand was met.

The judiciary committee officially requested the FBI investigation, saying it should probe current "credible allegations" against Kavanaugh. Republicans said it would be up to the FBI to decide what allegations were considered credible.

It was Flake, Alaska GOP Senator Lisa Murkowski and Maine GOP Senator Susan Collins who set the terms of the investigation, CNN said.

Kavanaugh, who denies all allegations against him, said that he would "continue to cooperate" with the FBI. He accused Democrats of politicising the process and harming his family and good name.

Three women, including Ford, have accused Kavanaugh of sexually assaulting them several decades ago.

Ford appeared at a judiciary committee hearing on Thursday to testify that Kavanaugh attempted to rape her in 1982 when both were teenagers.

Ford's lawyer Debra Katz welcomed the decision of calling for the probe but questioned the time limit of a week. "A thorough FBI investigation is critical to developing all the relevant facts... No artificial limits as to time or scope should be imposed on this investigation."