In a strongly worded eight-page letter delivered to House Speaker Nancy Pelosi (D-Calif.) and other top Democratic leaders on Tuesday, the White House strongly detailed why it will not participate in the Dems’ “illegitimate and unconstitutional” impeachment inquiry — and said “the proceedings have run roughshod over congressional norms and the president’s due-process rights,” as Fox News and other outlets noted on Tuesday afternoon.

Trump administration officials called the letter, written by White House counsel Pat Cipollone and obtained by Fox News, “perhaps the most historic letter the White House has sent.”

The letter may result in a collision course up ahead with congressional Democrats, noted Fox News; the Democrats have sent out a flurry of subpoenas in recent days.

The lawmakers claim President Donald Trump sought to get Ukraine — during a controversial July 25 phone call with the president of Ukraine that has been widely debated — to investigate former Vice President Joe Biden.

However, the president has said he has a duty to fight against corruption that could hurt the United States.

Related: Here’s How Much the ‘Whistleblower’ Really Knew About Trump’s Phone Call

“President Trump and his administration reject your baseless, unconstitutional efforts to overturn the democratic process,” the letter from the White House counsel stated in no uncertain terms.

“Your unprecedented actions have left the president with no choice. 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.”

Trump had earlier vowed to send such a letter.

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He had also questioned why no impeachment inquiry vote had been held as of yet.

“One of the most democratic things you can do in a democracy is to have your elected representative vote on issues important to the country,” said Sen. Lindsey Graham (R-S.C.) on Sunday during an interview with anchor Maria Bartiromo of Fox News’ ‘Sunday Morning Futures.”

“So it’s imperative that Democrats vote to open up articles of impeachment inquiry — not just talk about it. Don’t hide behind Nancy Pelosi,” added Graham.

The White House document sent on Tuesday finished with: “The president has a country to lead. The American people elected him to do this job, and he remains focused on fulfilling his promises to the American people.”

There has — at least as of now — been no formal vote in the House to open an impeachment inquiry against the president.

Related: See Which Democrat Was Booed at Town Hall for ‘Coup’ Against Trump 

That process would require lawmakers to go on the record with their views of impeachment and also allow the White House to mount a proper defense.

The counsel’s letter noted that the press conference held by Pelosi last month was not sufficient to begin any such impeachment proceedings against Trump.

The Democratic heads of three House committees had declared in a Friday letter that Trump “has chosen the path of defiance, obstruction, and cover-up” in response to the ongoing inquiry related to his phone conversation with the Ukraine president.

In the letter to acting White House Chief of Staff Mick Mulvaney, the three committee heads — Oversight Committee Chairman Elijah Cummings ( D-Md.), Intelligence Committee Chairman Adam Schiff (D-Calif.), and Foreign Affairs Committee Chairman Eliot Engel (D-N.Y.) — together gave the White House until October 18, exactly two weeks from now, to produce documents they’re seeking.

“We deeply regret that President Trump has put us — and the nation — in this position, but his actions have left us with no choice but to issue this subpoena,” the committee chairmen wrote.

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