The White House is pushing back against the House impeachment inquiry into President Donald Trump by refusing to cooperate with lawmakers’ demands for documents and interviews related to the investigation, setting up a constitutional crisis.

The eight-page letter, signed Tuesday by White House counsel Pat Cipollone, also accused Democratic lawmakers of using the investigation to overturn the 2016 election results and demanded they abandon all impeachment efforts.

The administration’s letter ― which consisted more of the president’s political attacks than substantive legal arguments ― alleged that Democrats have denied Trump the right to “see all evidence, to present evidence, to call witnesses, to have counsel present at all hearings, to cross-examine all witnesses” and to object to “the examination of witnesses or the admissibility of testimony and evidence.”

“President Trump and his Administration reject your baseless, unconstitutional efforts to overturn the democratic process. Your unprecedented actions have left the President with no choice,” the letter stated. “In order to fulfill his duties to the American people, the Constitution, the Executive Branch, and all future occupants of the Office of the Presidency, President Trump and his Administration cannot participate in your partisan and unconstitutional inquiry under these circumstances.”

The letter is addressed to House Speaker Nancy Pelosi, House Intelligence Chairman Adam Schiff (D-Calif.), House Foreign Affairs Chairman Eliot Engel (D-N.Y.) and House Oversight Chairman Elijah Cummings (D-Md.). Those three committees are in charge of the impeachment inquiry.

In response, Pelosi said Tuesday that the letter’s allegations are “manifestly wrong” and constitute the White House’s latest “unlawful attempt to hide” the Trump administration’s efforts to pressure foreign governments to intervene in the 2020 elections.

“The White House should be warned that continued efforts to hide the truth of the President’s abuse of power from the American people will be regarded as further evidence of obstruction,” Pelosi said in a statement. “Mr. President, you are not above the law. You will be held accountable.”

The White House’s refusal to cooperate at all is almost sure to wind up in court.

“The White House says there is nothing wrong with pressuring a foreign government to intervene in a US election,” Schiff tweeted in response to the Cipollone letter, which also attacked the congressman’s character. “They say: they will not cooperate with an impeachment inquiry unless it’s on their terms. They mean: the President is above the law. The Constitution says otherwise.”