Sen. Jeff Merkley, D-Ore., announced Wednesday that he is filing a lawsuit against President Trump and Senate Majority Leader Mitch McConnell, R-Ky., in a bid to prevent the Senate from taking up Brett Kavanaugh’s Supreme Court nomination until his “full record” is available.

“I’m suing [Trump] & [McConnell] today to stop the unconstitutional #KavanaughConfirmation process,” Merkley tweeted on Monday. “They may want to ram through this nomination come hell or high water, but that’s just not how our Constitution works.”

The statement came amid graphic new allegations that the nominee was involved in “gang” rapes in the 1980s, which Kavanaugh vehemently denies.

Merkley, who called Kavanaugh’s nomination “an assault on the separation of powers,” said he will be filing the lawsuit sometime on Wednesday in federal court in Washington, D.C., and that he wants the court to block a vote until all documents are handed over.

Speaking to reporters in Washington, Merkley acknowledged that he does not know of any precedent where a court blocked the Senate from voting, but added that he doesn’t recall a time where the White House had so “profoundly interfered” on a Supreme Court nominee’s documents.

“This is unchartered territory,” he said.

His office said the suit argues the defendants’ handling of the nomination violated the “separation of powers and the advice and consent clause,” by withholding documents.

Merkley’s announcement comes less than 24 hours before Kavanaugh and California professor Christine Blasey Ford are set to testify before the Senate Judiciary Committee about an alleged sexual assault while the two were in high school.

Earlier in the day, attorney Michael Avenatti also identified and released a “sworn declaration” from a woman who claims Kavanaugh was involved in “gang” rapes in the early 1980s.

Avenatti’s client was identified as Julie Swetnick, who further claims in the statement that Kavanaugh and a friend were “present” when she became a “victim of one of these ‘gang’ or ‘train’ rapes” in 1982.

Kavanaugh issued a strong denial in response, saying in a statement: “This is ridiculous and from the Twilight Zone. I don’t know who this is and this never happened.”

The Senate Judiciary Committee on Wednesday released Kavanaugh’s prepared testimony ahead of Thursday’s hearing. In it, Kavanaugh says he “never sexually assaulted anyone – not in high school, not in college, not ever.”

“Sexual assault is horrific,” he says. “It is morally wrong. It is illegal. It is contrary to my religious faith.”

Kavanaugh told Fox News in an interview broadcast Monday night that he has “always treated women with dignity and respect.”