President Donald Trump looks on during a campaign rally in Battle Creek, Michigan Reuters

President Donald Trump's request to block nearly $400 million in military aid from Ukraine was primarily driven by a small group of top officials despite concerns across budget and military offices.

A comprehensive investigation carried out by The New York Times found that Trump caused widespread confusion within the administration during the 84 days between when he first inquired about the funding package to his decision to call back the block in September.

Two officials identified by The Times as instrumental in supporting Trump's call to block aid have avoided impeachment proceedings, despite subpoenas from House Democrats.

Internal emails and testimonies could come under closer scrutiny as impeachment proceedings move to the Republican-majority Senate, which will hold a trial and most likely acquit the president.

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President Donald Trump's request to block nearly $400 million in military aid from Ukraine reportedly drove deep divisions between administration officials who were taken aback by the move.

A comprehensive investigation by The New York Times into the attitudes inside the administration during the 84 days between when Trump first inquired about the funding package to his decision to call back the block in September revealed tensions between top members of Trump's inner circle.

In addition to acting White House chief of staff Mick Mulvaney, Russell T. Vought, the acting head of the Office of Management and Budget, Robert Blair, the senior adviser to Mulvaney, and Mark Paoletta, the budget office's top lawyer were the main group of officials responsible for executing a secret effort "to bring pressure on a country [Trump] viewed with suspicion, if not disdain," The Times wrote.

'Expect Congress to become unhinged'

Acting chief of staff Mick Mulvaney listens as President Donald J. Trump participates in a working lunch with governors on workforce freedom and mobility in the Cabinet Room at the White House on Thursday, June 13, 2019 in Washington, DC. Jabin Botsford/The Washington Post via Getty Images

Early in Trump's inquiry about withholding funds The Times reported, that Blair wrote to Mulvaney in an email that the administration should "expect Congress to become unhinged" if the White House tried to pull back spending that was approved in Congress.

Blair also reportedly warned that the move might pile on to Trump's pro-Russia image, which has popped up in impeachment proceedings as a concern across the administration after Trump reportedly credited a debunked conspiracy theory for disliking Ukraine.

The Times reported that Vought had grown used to addressing unusual requests from Trump that had little to do with formal policy research by the time he identified an article by conservative outlet the Washington Examiner, which said that American security aid would total $1.5 billion between this year and 2014, as the trigger for Trump's request.

Divisions within the administration hardened as more reports surfaced over the aid block, evidenced by actions like then-national security adviser John Bolton, Secretary of Defense Mark Esper, and Secretary of State Mike Pompeo, who met with the president to privately urge him to release the funding, according to The Times.

Blair, who has since been elevated to special representative for international telecommunications policy, and Vought could become more prominent figures in the upcoming impeachment proceedings set to take place in the Republican-majority Senate, which will hold a trial and most likely acquit the president.

However, Democratic lawmakers have identified prominent officials who were instrumental in pushing the aid block, which created deep tensions within the administration's budget and military departments, The Times reports.

Mark Sandy was the only OMB official to testify in the impeachment inquiry and he identified Mike Duffey, Trump's appointed associate director for national security programs in the Office of Management and Budget, as having abruptly taken over authority in signing off on documents that concerned aid for Ukraine, which he said made his staff "surprised" and "concerned."

Like Duffey, Vought and Blair were subpoenaed for testimony but defied the orders.

Republican lawmakers have publicly called for a quick trial with no witnesses, but Senate Majority Leader Mitch McConnell said he would follow cues from White House counsel.

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