A whistleblower's complaint about President Donald Trump, made public on Thursday, says White House officials were so concerned about what the president said in a July call with Ukraine's new leader that they intervened to "lock down" the transcript of the conversation.

The whistleblower, whose name and gender has not been released, lodged the formal complaint out of a belief that Trump was "using the power of his office to solicit interference from a foreign country" in the 2020 election.

In the call, Trump discussed having Ukrainian President Volodymyr Zelenskiy help investigate the Biden family's business dealings. The matter is now the subject of a formal impeachment inquiry that was launched by the House this week.

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"The interference includes, among other things, pressuring a foreign country to investigate one of the president's main domestic political rivals," the whistleblower wrote. "The president's personal lawyer, Mr. Rudolph Giuliani, is a central figure in this effort. Attorney General (William) Barr appears to be involved as well."

The complaint, which was made public with minimal redactions, makes clear there are witnesses who can back up the account, and it indicates concern over the internal handling of the White House record of the phone call.

The whistleblower says White House officials told them the conversation on July 25 between Trump and Zelenskiy was removed from the computer system that is typically used for such records of calls with foreign leaders.

Instead, the whistleblower writes, the transcript was loaded into a separate electronic system that is used only for information that is of an "especially sensitive nature." One White House official described that as an abuse of the secure system because there was nothing "remotely sensitive" on the phone call from a national security perspective, the whistleblower said.

According to White House officials the whistleblower spoke with, that was "not the first time" the Trump administration placed a presidential transcript "into this codeword-level system solely for the purpose of protecting politically sensitive — rather than national security sensitive — information."

The nine-page complaint includes inside information from a number of White House and administration officials, in addition to accounts from previously published stories in the media.

The whistleblower said the actions described in the complaint posed "risks" to national security and undermined efforts to counter foreign interference.

The whistleblower wrote that "over the past four months, more than half a dozen U.S. officials have informed me of various facts related to this effort," referring to soliciting foreign interference in the American election.

"I was not a direct witness to most of the events described," the whistleblower continued. "However, I found my colleagues' accounts of these events to be credible because, in almost all cases, multiple officials recounted fact patterns that were consistent with one another."

The whistleblower said Trump's actions constituted a "serious or flagrant problem, abuse, or violation of law or Executive Order."

Trump sought to pressure Zelenskiy, the whistleblower wrote, to take actions that would boost the president's 2020 election bid, which included probing former Vice President Joe Biden and his son Hunter, and communicating with Giuliani and Barr.

White House officials told the whistleblower they were "deeply disturbed" with the president's actions.

Concerning Giuliani's actions, the whistleblower said that beginning in mid-May, "I heard from multiple U.S. officials that they were deeply concerned by what they viewed as Mr. Giuliani's circumvention of national security decision-making processes to engage with Ukrainian officials and relay messages back and forth between" Ukrainian leaders and Trump.

The officials told the whistleblower that State Department officials spoke with Giuliani "in an attempt to 'contain the damage' to U.S. national security."

Speaking with CNN on Thursday, Giuliani denied the allegations, saying he had "no knowledge of any of that crap" and calling the charge that U.S. officials were concerned about his actions "total nonsense."

"At no time did" the State Department officials "say they wanted to contain damage," Giuliani told CNN. "At no time did the State Department in communication with me ever relay any of that information you're talking about."

Multiple U.S. officials told the whistleblower that Ukrainian leadership believed that a phone call or meeting between Zelenskiy and Trump was contingent on the Ukrainian president's willingness to "play ball" on the issues that could prove politically beneficial to Trump. U.S. officials said it was "made clear" to them that Trump did not want to meet with Zelenskiy until he saw how Zelenskiy "chose to act" in office, the whistleblower wrote.

The whistleblower also wrote of learning about a "sudden change of policy with respect to U.S. assistance for Ukraine" in mid-July that executive branch officials could not explain.The Trump administration froze nearly $400 million in aid to Ukraine, releasing that hold just before Democrats in Congress revealed the existence of the whistleblower complaint.

According to the complaint, officials with the Office of Management and Budget "again stated explicitly that the instruction to suspend this assistance had come directly from the President, but they still were unaware of a policy rationale."

The whistleblower's complaint was supposed to have been turned over to Congress within a week, but acting Director of National Intelligence Joseph Maguire refused to do so on the advice of the Justice Department. Maguire testified publicly before the House Intelligence Committee on Thursday.

During a tense hearing with lawmakers, Maguire defended his initial decision not to give Congress the complaint because the allegation contained "secondhand information." He said he wanted "further clarification" from the White House, but "at no time was there ever intent on my part to withhold the complaint from you."

"The question came down to 'urgent concern,' which is a legal definition," he said. “I was just trying to work through the law the way it was written."

Maguire also said he found the complaint "credible" and that he believes the whistleblower acted lawfully and "is on our country’s side."

Soon after the complaint was released, White House press secretary Stephanie Grisham said in a statement that "nothing has changed," adding the document was "nothing more than a collection of third-hand accounts of events and cobbled-together press clippings — all of which shows nothing improper."

"The President took the extraordinary and transparent steps of releasing the full, unredacted, and declassified transcript of his call with President Zelenskiy, which forms the heart of the complaint, as well as the complaint itself," Grisham said. "That is because he has nothing to hide."

Earlier Thursday, Trump went off on an extensive tweetstorm.

"THE GREATEST SCAM IN THE HISTORY OF AMERICAN POLITICS!" Trump wrote. Moments earlier, he responded to a photo his daughter Ivanka, a top White House official, posted Wednesday, writing: "So cute!"

"Her father is under siege, for no reason, since his first day in office!" he added.

Meanwhile, House Speaker Nancy Pelosi, D-Calif., who had for months resisted the growing number in her caucus who advocated for impeachment, told top Democrats in a closed-door meeting Wednesday morning she wants to narrow the scope of the impeachment inquiry into Trump by focusing on his interaction with his Ukrainian counterpart, multiple sources told NBC News. Those sources cautioned that no firm decision has been made.

Two House leadership sources told NBC News that Pelosi prefers to focus on the Ukraine issue, as she views the alleged underlying bad act to be simple and straightforward. Pelosi believes the Ukraine issue provides the strongest case to quickly build public support for impeachment, which is one of her chief goals, the sources said.

The White House released a summary of the president's discussion with Zelenskiy Wednesday — a summary that showed Trump asked the Ukrainian president to look into why that country's top prosecutor apparently had ended an investigation of the business dealings of Joe Biden’s son, who served on the board of a Ukrainian gas company.

At another point in the call, Trump appears to ask Zelenskiy whether someone in the Ukraine might possess a server that contained some of former presidential candidate Hillary Clinton’s emails.

“I would like you to do us a favor, though, because our country has been through a lot and Ukraine knows a lot about it. I would like you to find out what happened with this whole situation with Ukraine. They say CrowdStrike … I guess you have one of your wealthy people … the server, they say Ukraine has it,” Trump said on the call, according to the call summary.

Though it was not explicit, Trump also appears to tie the award of aid to Ukraine to Zelenskiy's willingness to cooperating with Trump.

"I will say that we do a lot for Ukraine. We spend a lot of effort and a lot of time. Much more than the European countries are doing," Trump says in the description, adding the U.S. "has been very, very good to Ukraine."

"I wouldn't say that it's reciprocal necessarily because things are happening that are not good, but the United States has been very, very good to Ukraine," he continued.