WASHINGTON — The Democratic-led House Intelligence Committee released a report Tuesday containing a summary of the evidence it has collected in the impeachment inquiry into President Donald Trump.

The 300-page report cited two instances of improper conduct: obstruction of the House inquiry and withholding an official White House meeting and military aid from Ukraine on the condition of investigating a Trump political rival.

On obstruction, which was described as a “campaign of intimidation,” the report cast Trump’s efforts to “flout” Congress oversight as unprecedented because of his refusal to hand over documents and make certain witness available. But it also noted that “the House gathered overwhelming evidence of his misconduct from courageous individuals who were willing to follow the law.”

“No other President has flouted the Constitution and power of Congress to conduct oversight to this extent,” the report said.

“If left unanswered, President Trump’s ongoing effort to thwart Congress’ impeachment power risks doing grave harm to the institution of Congress, the balance of power between our branches of government, and the Constitutional order that the President and every Member of Congress have sworn to protect and defend.”

The report also constructed a timeline of Trump’s alleged efforts to withhold military assistance to Ukraine, as well as an official White House meeting with Trump, based on the testimony of various aides and diplomats who have been questioned by impeachment investigators.

“In making the decision to move forward, we were struck by the fact that the President’s misconduct was not an isolated occurrence, nor was it the product of a naïve president,” the report said.

“President Trump does not appear to believe there is any such limitation on his power to use White House meetings, military aid or other official acts to procure foreign help in his reelection.”

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The release came ahead of a meeting scheduled for 6 p.m. ET Tuesday for the panel to consider and vote on adopting the report. The report, along with views provided by Republicans, will then be sent to the House Judiciary Committee, which is taking over the next phase of the inquiry.

Members of the committee began reviewing the majority report Monday evening. Lawmakers were allowed to only look through the draft report behind closed doors in committee spaces.

The report focused on the findings by the Intelligence Committee in the Ukraine case — whether Trump pressured Ukraine to investigate former Vice President Joe Biden and his son Hunter Biden as well as a debunked conspiracy theory about the 2016 presidential election as the U.S. dangled taxpayer funding to Ukraine and a White House meeting for its leader in exchange.

Over two weeks of public hearings last month, a number of the 12 witnesses who testified confirmed and elaborated on the efforts allegedly made by Trump, his associates and administration officials to get Ukraine to announce investigations into those two issues, and why they believed delayed U.S. aid to Ukraine would only be released once that nation followed through on those demands.

Gordon Sondland, the U.S. ambassador to the E.U., told lawmakers that he, former Energy Secretary Rick Perry and former U.S. special envoy to Ukraine Kurt Volker “followed the president’s orders” to work with Rudy Giuliani, Trump’s personal attorney, on Ukraine policy.

Several witnesses also testified about a phone conversation between Sondland and the president that took place a day after the July 25 phone call between Trump and Ukrainian President Volodymyr Zelenskiy, in which Trump allegedly asked Sondland if Zelenskiy was “gonna do the investigation.”

Republicans on the House Intelligence, Oversight, and Foreign Affairs committees released a 123-page minority report Monday evening that argues that Democrats have failed to establish any impeachable offenses by Trump. They said that they didn’t find that Trump engaged in any wrongdoing, and that there was no quid pro quo.

“The Democrats’ impeachment inquiry, led by House Intelligence Committee Chairman Adam Schiff, is merely the outgrowth of their obsession with re-litigating the results of the 2016 presidential election,” the Republicans said in their report.

“Despite their best efforts, the evidence gathered during the Democrats’ partisan and one-sided impeachment inquiry does not support that President Trump pressured Ukraine to investigate his political rival to benefit the President in the 2020 presidential election. The evidence does not establish any impeachable offense,” they wrote.

Republicans said there was no evidence that Trump improperly withheld $391 million in military aid to Ukraine or pressured President Zelenskiy to investigate Joe Biden to help benefit his 2020 re-election campaign, arguing that much of Trump’s action regarding Ukraine actually stems from his “longstanding” skepticism of the country due to “its history of pervasive corruption.”

On Wednesday, the House Judiciary Committee is expected to hold its first impeachment hearing, which its chairman, Rep. Jerrold Nadler, D-N.Y., said will “explore the framework put in place to respond to serious allegations of impeachable misconduct like those against President Trump.”

Nadler extended an invitation to Trump and his counsel to participate in Wednesday’s hearing, but the White House said Sunday that they declined the offer. The president is in London this week for the 2019 NATO summit.

The report from the intelligence panel comes after Intelligence Committee members, along with lawmakers from the House Oversight and Foreign Affairs committees, conducted 17 closed-door interviews with key witnesses in the impeachment inquiry. Before the Thanksgiving break, the Intelligence Committee then held public hearings with a dozen of those witnesses.

It has not yet been decided how many hearings Judiciary might hold or what charges potentially might be wrapped into articles of impeachment. Some lawmakers have recently raised the possibility that other cases could be considered, such as those stemming from former special counsel Robert Mueller’s report on Russian interference in the 2016 election.

Haley Talbot contributed.