Donald Trump was briefed on the whistleblower complaint about his dealings with Ukraine before the White House released nearly $400m in military aid to Kyiv, officials said on Wednesday, shedding new light on events that triggered the impeachment inquiry.

The president was told about the complaint in late August in a briefing by the White House counsel, Pat Cipollone, and John Eisenberg, an attorney with the White House national security council, according to two officials not authorized to publicly discuss the matter.

The lawyers told Trump about the complaint, explaining that they were trying to determine whether they were legally required to give it to Congress, the officials said. The aid was released on 11 September amid growing pressure from members of Congress.

The White House did not immediately respond to a request for comment on Wednesday.

The White House has claimed there was no link between the military aid suspension and Trump’s request for Ukraine to investigate his political rival Joe Biden and his family.

But it was his request to Ukraine’s president, Volodymyr Zelenskiy, in a July phone call that prompted the government whistleblower’s complaint about a link. The assertion of such a link has since been corroborated by a parade of witnesses testifying on Capitol Hill during closed-door and public hearings in the impeachment inquiry to date.

The August briefing with Trump was first reported by the New York Times.

The revelation comes just days before the House judiciary committee takes over the impeachment inquiry, scheduling a hearing for next week as it pushes closer to a possible vote on charges of high crimes and misdemeanors and a congressional trial for the president in the Senate.

Trump has been invited to attend the hearing, but is not widely expected to turn up.

The judiciary panel scheduled the hearing as the intelligence committee on Tuesday released two last transcripts from its depositions, including from a White House budget official who detailed concerns among colleagues as Trump ordered them, through intermediaries, to put a hold on military aid to Ukraine.

The transcripts released on Tuesday evening revealed that a lawyer for the White House’s budget office resigned partly because of concerns overTrump’s freeze on the military aid to Ukraine, according to a longtime career official from the office who had testified to Congress behind closed doors.

Mark Sandy of the Office of Management and Budget (OMB) told the House of Representatives’ impeachment inquiry that an individual in the office’s legal division quit in part over issues with the suspension of security assistance to Ukraine, according to a transcript of his deposition released on Tuesday.

Sandy also testified that another unnamed official at the OMB resigned. “Yes, this individual did express frustrations,” he said. “He expressed some frustrations about not understanding the reason for the hold.”

In a further sign of pushback, the Pentagon raised concerns, Sandy added.

Sandy also recalled that he was told on 19 June Trump had raised questions about the military aid to Ukraine after reading a media report. He was then informed in an email on 12 July that Trump himself “is directing a hold on military support funding for Ukraine” but given no explanation or justification.

Meanwhile, it emerged that Rudy Giuliani, Trump’s personal lawyer, was pursuing business opportunities from Ukrainian officials while pressuring the country to investigate Biden and a conspiracy theory that Ukraine interfered in the 2016 US election to help Hillary Clinton.

Documents indicate Giuliani privately pursued lucrative deals, despite denying any business in Ukraine, the New York Times reported.