WASHINGTON (Reuters) - President Donald Trump, under intense pressure from moderates in his own party over his Supreme Court nominee, on Friday ordered an FBI investigation into sexual misconduct allegations against Brett Kavanaugh at the request of Senate Republicans, a move that will delay the contentious confirmation process by a week.

The key player in a day of dramatic and unexpected developments was Senator Jeff Flake, a moderate Republican retiring from the Senate in January who provided the decisive vote to approve Kavanaugh’s nomination in the Judiciary Committee and send the matter to the full Senate.

But Flake, after urgent consultations with colleagues including Democratic Senator Chris Coons, cast the vote only after asking the Republican-led panel to request that the Trump administration pursue an FBI probe lasting up to seven days of the explosive allegations against Kavanaugh.

Trump, who had previously rebuffed Democratic demands for an FBI probe, granted the request, ordering the “supplemental investigation” to be “limited in scope and completed in less than one week.”

“Just started, tonight, our 7th FBI investigation of Judge Brett Kavanaugh. He will someday be recognized as a truly great Justice of The United States Supreme Court!,” Trump said in a Twitter post late on Friday.

Flake’s move came a day after an extraordinary hearing in which university professor Christine Blasey Ford detailed her sexual assault allegation against Kavanaugh. Flake’s action also came only hours after two protesters who said they were sexual assault survivors cornered him in an elevator and castigated him for announcing he would vote for Kavanaugh in the committee.

“That’s what you’re telling all women in America - that they don’t matter, they should just keep it to themselves,” one of the protesters shouted at Flake, a frequent Trump critic who looked shaken by the encounter.

Flake, who had a pained expression when he made his request for an FBI probe in the committee after forcing a brief delay in the scheduled vote, was supported by two other Republican moderates, Lisa Murkowski and Susan Collins, both of whom have not announced whether they would support Kavanaugh.

The allegations against Kavanaugh, with the backdrop of the #MeToo movement against sexual harassment and assault that has toppled a succession of powerful men, have riveted the country even as they have imperiled his confirmation chances.

Trump’s nomination of Kavanaugh, a conservative federal appeals court judge, for a lifetime job on the top U.S. court had appeared to be going along smoothly until Ford’s allegation surfaced last week. He has denied her allegation and accusations of sexual misconduct made by two other women.

The committee vote followed a jarring and emotional hearing on Thursday in which Ford accused Kavanaugh of sexually assaulting her in 1982 when both were high school students in Maryland. Kavanaugh denied the accusation and accused Democrats - who have opposed his nomination from the outset - of a “calculated and orchestrated political hit.”

In a statement issued by the White House, Kavanaugh said he would cooperate with the FBI investigation.

If confirmed, Kavanaugh would consolidate conservative control of the nation’s highest court and advance Trump’s broad effort to shift the American judiciary to the right.

The controversy has unfolded just weeks ahead of the Nov. 6 congressional elections in which Democrats are trying to seize control of Congress from the Republicans.

‘RIPPED APART’

“This country’s being ripped apart here,” Flake told his fellow senators about the nomination fight. “I think we can have a short pause,” he added.

“We ought to do what we can to make sure that we do all due diligence with a nomination this important,” Flake said.

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Even before Flake’s move, it was unclear if Republicans had the votes to confirm Kavanaugh on the Senate floor. Republicans hold a slim 51-49 majority in the Senate, making the votes of Murkowski and Collins crucial. Trump can afford to lose the vote of only one senator in his own party if all the Democrats vote against Kavanaugh and Vice President Mike Pence casts a tie-breaking vote.

Trump said Murkowski and Collins must do what they think is right. Moderate Democrats Joe Manchin and Heidi Heitkamp, who have not yet announced how they will vote on Kavanaugh, also supported Flake’s move.

Trump indicated he was sticking with Kavanaugh, saying he has not thought “even a little bit” about replacing him.

With tempers flaring, the Judiciary Committee advanced the nomination 11-10 along party lines. The Senate formally moved to open debate on Kavanaugh’s nomination later on Friday in a move agreed to by both parties, setting the stage for a planned final vote on confirmation at the end of next week.

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“This is a nomination that deserves to move forward,” Senate Majority Leader Mitch McConnell said.

Ford’s lawyer, Debra Katz, welcomed the FBI investigation and thanked the senators who pushed for it but decried the limits imposed on it. “A thorough FBI investigation is critical to developing all the relevant facts,” Katz said.

The timing of the panel’s session gave committee members little time to digest Thursday’s remarkable testimony from Kavanaugh and Ford. Trump said he found Ford’s testimony “very compelling” and Kavanaugh’s angry and defiant response “incredible.”

Before Flake’s move, committee Republicans voted down a Democratic motion seeking to subpoena Mark Judge, a Kavanaugh friend who Ford said witnessed the assault. Judge had told the committee in a written statement he does not recall any such incident. He is likely to be central to any FBI probe.

Judge’s lawyer said he would cooperate with the FBI or any other law enforcement agency.

As the committee set its vote, some Democrats left the room in protest. “What a railroad job,” Democratic Senator Mazie Hirono said. One Republican, Senator John Kennedy, called Kavanaugh’s confirmation process “an intergalactic freak show.”

Senator Dianne Feinstein, the committee’s senior Democrat, called Kavanaugh’s testimony unseemly for a judicial nominee.

“This was someone who was aggressive and belligerent. I have never seen someone who wants to be elevated to the highest court in the country behave in that manner. In stark contrast, the person who testified yesterday and demonstrated a balanced temperament was Dr. Ford,” Feinstein said.

The American Bar Association, which earlier endorsed Kavanaugh, and the dean of Yale Law School, which Kavanaugh attended, also called for an FBI probe on Friday, the first indication of the legal profession turning on the nominee.

Kavanaugh could be the deciding vote on contentious legal issues if he is confirmed to the nine-member court, with disputes involving abortion, immigration, gay rights, voting rights and transgender troops possibly heading to the court soon. The court begins its next term on Monday.