Senate Majority Leader Mitch McConnell, R-Ky., refused a request Wednesday by Senate Minority Leader Chuck Schumer, D-N.Y., for senators to receive an FBI-led briefing on its investigation into Supreme Court nominee Brett Kavanaugh.

Schumer asked that the FBI agents charged with conducting a supplemental background check into Kavanaugh amid multiple allegations of sexual misconduct talk to senators about their findings before a vote on the judge's confirmation in both a Tuesday letter and a speech on the Senate floor Wednesday.

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McConnell responded in a letter to his counterpart that such a briefing would be "unprecedented and irregular" under the memorandum of understanding between the Senate Judiciary Committee and the White House that governs how the results of background investigations for judicial nominees are handled.

But McConnell blasted Schumer's call as another obstruction tactic leveled by Democrats in the upper chamber.

"And, in all candor, I believe it would be used to further delay this nomination — a goal about which and your Democratic colleagues have been abundantly clear and single-minded in pursuing," McConnell added.

Kavanaugh's nomination was delayed for up to a week when Sen. Jeff Flake, R-Ariz., told the Senate Judiciary Committee he could not support the judge's candidacy without the FBI looking at claims of sexual misconduct dating back to the 1980s.