The Democratic staff of the Judiciary Committee did not immediately respond to a request for comment on the White House's refusal to participate in the hearing, which would have been the first direct involvement of the Trump camp in a process that the president has condemned as a " Witch hunt, quot; ".
In a 5-page letter released Sunday evening, Pat Cipollone, the White House counsel, declined an offer extended by Judiciary Committee Chairman Rep.
In his letter, Cipollone accused Nadler, a New York Democrat, of purposely scheduling the hearing so that it will run concurrently with Trump's trip to London for a North Atlantic Treaty Organisation summit.
Their exact findings are not publicly known, but the report is expected to lay out a case for Trump's abuse of his presidential powers - that he used the promise of a White House meeting and the withholding of military aid approved by Congress to compel Ukraine's government to launch politically motivated investigations into his political rivals.
President Trump also blasted Democrats for the unfair process in a tweet on Saturday night and accused the House of intentionally scheduling the proceedings while he is overseas.
Jerry Nadler (D-N.Y.), the committee's chairman, has asked Collins whether Republicans want to subpoena any witnesses to testify on behalf of Trump.
The hearing on Wednesday marks the next stage in the impeachment inquiry, which centres on a July phone call between Mr Trump and Ukrainian President Volodymyr Zelensky.
The evidence does not establish that President Trump pressured Ukraine to investigate Burisma Holdings, Vice President Joe Biden, Hunter Biden, or Ukrainian influence in the 2016 election.
Trump claims that he has done nothing wrong and, while the House puts forward an ambitious timetable for a vote to dismiss, the President and his Republican allies are aligning against the process.
Rep. Tom McClintock, R-Calif., a member of the Judiciary Committee, said on "This Week" that he thought it "would be to the president's advantage" to have counsel participate in the upcoming hearings. Many found ways to cover them other ways, by entering as members of the public.
This comes as the impeachment inquiry into President Trump is moving into its next phase.
The impeachment inquiry has heard testimony from current and former officials that military aid was withheld from Ukraine and that a White House meeting with Ukrainian President Volodymyr Zelenskiy was conditioned on investigations into the Bidens and a debunked conspiracy theory about interference in the 2016 USA election being carried out.
"The first and foremost person who needs to testify is Adam Schiff", Collins said while adding that Schiff had "compared himself to a special counsel". Democratic House Speaker Nancy Pelosi, who will make the final decision, has not said yet whether the Republican president should be formally impeached. "I am fighting for future Presidents and the Office of the President. I really think you can handle your own newsroom of immensely talented editors and reporters covering you the same way they do everything else".
Senate Majority Leader Mitch McConnell, R-Ky., has said that it's "inconceivable" that there are the votes in the Senate to convict and remove the president - a two-thirds majority would be needed (67 votes).