A former senior Department of Justice official will testify on Friday before the congressional committee investigating the Capitol insurrection by extremist supporters of Donald Trump, a congressional aide familiar with the inquiry has said.

Last week, the House of Representatives select committee delayed testimony by Jeffrey Clark because he had retained a new lawyer.

Clark did not immediately respond to requests from Reuters for comment. The congressional aide spoke on condition of anonymity.

Clark, the former acting head of the DoJ’s civil division, was a proponent Trump’s false claims that Joe Biden’s victory in the November election was the result of fraud.

On 13 October, the committee announced it had issued a subpoena to Clark asking him to produce records and testify at a deposition by 29 October.

In announcing it had subpoenaed Clark, the panel said it needed to understand all the details about efforts inside the previous administration to amplify misinformation about election results.

In January, the DoJ’s inspector general announced his office was launching an investigation into whether Clark plotted to oust then acting attorney general Jeff Rosen so he could take over the department and help pursue Trump’s baseless claims by opening an investigation into voter fraud in Georgia.

A US Senate judiciary committee report found Clark also drafted a letter he wanted Rosen to approve which urged Georgia to convene a special legislative session to investigate voter fraud claims.

Clark’s plan ultimately failed after senior department leaders threatened to resign in protest, the Senate investigation found.

Meanwhile, former Trump White House chief of staff Mark Meadows and other top aides subpoenaed by the committee have defied orders to produce relevant documents and give testimony.

Four Trump aides targeted by the select committee – Meadows, deputy chief of staff Dan Scavino, strategist Steve Bannon and defense department aide Kash Patel resisted the orders – under the influence of Trump, sources told the Guardian last month.

The House later voted to hold Bannon in criminal contempt of Congress and federal prosecutors are weighing the case.