The Democratic-led House of Representatives Judiciary Committee, tasked with considering charges known as articles of impeachment, has given the president until 6 p.m. EST (2300 GMT) on Sunday to say whether he or his legal counsel will participate in an impeachment hearing on Wednesday.
"This is a complete American waste of time right here", he said.
"It's easy to hide behind a report", Collins added.
Democrats claim Trump called Ukrainian President Volodymyr Zelensky on July 25 and pressured him to launch an investigation into allegations that Ukraine meddled in the 2016 election and into former Vice President Joe Biden's action to have the country's top prosecutor fired.
The expected release of the report, coming 11 days after the last public hearing conducted by the Intelligence Committee, continues a breakneck pace for House Democrats as they investigate the potential impeachment of the president.
But Collins continued to defend Trump.
"I will be representing our Country in London at North Atlantic Treaty Organisation, while the Democrats are holding the most ridiculous Impeachment hearings in history".
The vote, probably to split across party lines, is a formality permitting the Democrat-controlled body to maneuver the impeachment question to the Judiciary Committee, which is scheduled to start its proceeding Wednesday. "Read the Transcripts, NOTHING was done or said wrong!"
Collins attacked the speedy timeline that Democratic leaders are pursuing, one that appears aimed at concluding an impeachment vote in the House before Christmas rather, he argued, than providing appropriate due process for the president.
He tweeted Saturday: 'I will be representing our Country in London at North Atlantic Treaty Organisation, while the Democrats are holding the most ridiculous Impeachment hearings in history. Hearings scheduled on same dates as NATO!' The informal hearing will examine the "constitutional grounds for presidential impeachment".
The Judiciary Committee is slated to hold its first impeachment hearing on December 4.
On Friday, Nadler gave The White House a week to decide whether it will send its attorneys to participate in the next set of hearings that he will oversee.
"To ensure fairness and restore integrity to the ongoing impeachment process, I request an expanded panel and a balanced composition of academic witnesses to opine on the subject matter at issue during the hearing", Collins wrote in a letter to committee chairman Jerrold Nadler on Saturday.
When asked why it could not have been two witnesses for each side, Jeffries stated, "Well that's something to be discussed", but then shifted to discussing the Trump appointees who previously testified before the House Intelligence Committee.
"I think it would be to the president's advantage to have his attorneys there".
Collins on Sunday renewed calls for Schiff personally to testify, indicating that he would face intense questioning from Republicans on the role his committee played in shepherding the whistleblower complaint that exposed Trump's irregular dealings with Ukraine, among other matters.
"They want to ... play a political game and tie the process up in the courts as long as they can and run the clock out", she said.