Updated at 7:30 p.m. ET

A government whistleblower received information from "multiple" officials that President Trump "is using the power of his office to solicit interference from a foreign country in the 2020 U.S. election."

An unclassified version of the whistleblower's complaint, made public Thursday by the House intelligence committee, says that the president's lawyer, Rudy Giuliani, "is a central figure in this effort. Attorney General [William] Barr appears to be as well."

The complaint centers on Trump's July 25 call with the president of Ukraine, an account of which was released Wednesday by the White House. That memorandum shows Trump asking the Ukrainian President Volodymyr Zelenskiy for "a favor" — to investigate potential 2020 rival former Vice President Joe Biden.

What the complaint released Thursday further reveals is that the whistleblower was told by officials that the record of the call was handled differently than other such transcripts. It was placed in an electronic system that is used to store especially sensitive classified information. Also, officials told the whistleblower this was not the first time that such an action had taken place for apparently political, rather than security, reasons.

Trump and the White House dismissed the complaint and stood by the phone call. Democratic lawmakers, meanwhile, have new threads to pursue with an ongoing impeachment inquiry.

What the complaint says

The whistleblower says that during the call, Trump "sought to pressure the Ukrainian leader to take actions to help the president's 2020 reelection bid."

According to the whistleblower, White House officials were "deeply disturbed by what had transpired in the phone call."

The complainant said that afterward, "senior White House officials had intervened to lock down all records of the phone call," which the whistleblower says "underscored to me that White House officials understood the gravity of what had transpired in the call."

The whistleblower said that, according to officials, this "was not the first time" that a presidential transcript was placed into a "codeword-level system solely for the purpose of protecting politically sensitive — rather than national security sensitive — information."

Translation: White House officials added security to restrict the circle of people who might be able to view them.

That is likely to raise questions about just what other information might be so protected relating to Trump's other conversations with foreign leaders.

White House pushes back

On Thursday, Trump repeated his characterization of the call with his Ukrainian counterpart as "perfect."

He said Democrats' investigation of the call and related activities "shouldn't be allowed. There should be a way of stopping it. Maybe legally through the courts."

Earlier, Trump harshly denounced those who provided the details of the White House activities pertaining to the call to the whistleblower.

According to an account in the Los Angeles Times, Trump told a private gathering of U.S. United Nations staff Thursday in New York, "I want to know who's the person, who's the person who gave the whistleblower the information? Because that's close to a spy," Trump said.

"You know what we used to do in the old days when we were smart? Right? The spies and treason, we used to handle it a little differently than we do now."

Three House chairmen whose committees are involved in the investigation — Foreign Affairs' Eliot Engel, Intelligence's Adam Schiff and Oversight and Government Reform's Elijah Cummings — issued a statement Thursday evening saying Trump's comments had crossed a line into "reprehensible witness intimidation and an attempt to obstruct Congress' impeachment inquiry."

"Threats of violence from the leader of our country have a chilling effect on the entire whistleblower process, with grave consequences for our democracy and national security," the chairmen said in the statement.