WASHINGTON — The House Rules Committee voted along party lines to approve six hours of debate on the House floor Wednesday as lawmakers vote on two articles of impeachment against President Donald Trump.

Democrats and Republicans will have three hours apiece to make their case ahead of votes.

"Congress has no other choice but to act with urgency," Chairman Jim McGovern, D-Mass., said earlier. McGovern said it "shocks" him that Republicans have not condemned the president's behavior.

"I get it — it's hard to criticize a president who's a member of your own party," he said, but added, "Moments like this call for more than just reflexive partisanship."

McGovern summarized the case against the president and said, "If that is not impeachable conduct, I don't know what is."

"To not act would set a dangerous precedent," he said. "The evidence is clear as it is overwhelming."

Rep. Tom Cole, R-Okla., the panel's ranking member, said there was no way the case to impeach the president could be viewed as legitimate.

"This is not the result of a fair process and certainly not a bipartisan one," said Cole, adding that "the majority is seeking to remove the president over something that didn't happen," a reference to the alleged quid pro quo over Ukraine aid at the heart of the impeachment inquiry.

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Numerous witnesses who testified in the inquiry told lawmakers that Trump and his associates leveraged U.S. military assistance and a White House meeting for Ukrainian President Volodymyr Zelenskiy in exchange for announcing investigations into former Vice President Joe Biden and his son Hunter Biden, as well as a debunked 2016 conspiracy theory.

Two members of the House Judiciary Committee, Reps. Jamie Raskin, D-Md., and Doug Collins, R-Ga., the Judiciary's ranking member, testified first at the meeting before the powerful Rules Committee, the final stop for legislation before it reaches the floor.

"These articles charge that the president is engaged in systematic abuse of powers," Raskin said.

"We present you not just with high crimes and misdemeanors but a constitutional crime in progress, up to this very minute," he said, referring to Rudy Giuliani's plans to present information that he gathered on his latest trip to Ukraine to the Trump administration.

Collins accused Democrats of having "cherry-picked the evidence" to support the case against the president, saying Trump and Zelenskiy "said there was no pressure" to launch probes against Democrats.

Judiciary Committee Chairman Jerry Nadler, D-N.Y., who had been expected to testify, missed the meeting Tuesday because of a family emergency, according to a committee aide, who said the committee was hopeful he would return for the impeachment debate on the House floor on Wednesday.

As the Rules meeting was underway Tuesday, the White House released a six-page letter that Trump sent to House Speaker Nancy Pelosi, D-Calif., in which he slammed the impeachment effort, "cheapened the importance of the very ugly word, impeachment” and said she was “declaring open war on American Democracy."

A number of freshman Democrats who flipped districts last year and face tough re-election fights also came out in support Tuesday of the articles of impeachment on the eve of the historic floor votes.

The Tuesday meeting marked a new process for the House, as the articles during the impeachment of President Bill Clinton did not come before the Rules Committee.

It follows the House Judiciary Committee's release of a comprehensive 658-page report on the impeachment of the president early Monday laying out the majority's case for why Trump should be removed from office for abuse of power and obstruction of Congress.

After a marathon markup last week, members of that panel voted along party lines to recommend that the full House consider the articles against the president.

The pivotal votes this week cap weeks of damaging testimony from witnesses who told Congress of the president’s efforts to pressure Ukraine into launching investigations of the Bidens and Democrats.

If the House votes Wednesday to impeach Trump, as expected, the process then moves to the Senate, which would then hold a trial early next year. Democrats are urging Senate Republicans to subpoena four key witnesses for their testimony in the Ukraine case.

Senate Majority Leader Mitch McConnell, R-Ky., told Sean Hannity on Fox News last week that there was "no chance" the Senate would reach the two-thirds vote necessary to convict the president.