Former Overstock CEO and Trump ally Patrick Byrne is set to speak to investigators for the House Select Committee investigating the attack on the US Capitol on January 6, 2021.
Mr Byrne is expected to meet with the committee on Friday, CNN reported.
The meeting will take place behind closed doors and no rules or areas of discussion have been set.
Mr Byrne actively supported the efforts to overturn the 2020 election and the spreading of false claims about the vote.
In December 2020, Mr Byrne attended a meeting at the White House to discuss ideas concerning how to reverse President Joe Biden’s election victory and how to keep former President Donald Trump in office.
The meeting was also attended by Mr Trump’s first national security adviser Michael Flynn and his attorney Sidney Powell, in addition to White House staffers.
The meeting focused on ways to stop the certification of Mr Biden’s victory and the possibility of seizing voting machines.
White House officials criticized the suggestions in the meeting, according to CNN.
In his interview with the January 6 committee last week, former White House counsel Pat Cipollone was asked about the gathering, which took place on 18 December.
Parts of that interview are expected to be revealed during the panel’s next hearing at 1pm on Tuesday.
The hearing will be aimed at connecting Mr Trump’s efforts to overturn the election and how “all the elements came together” and eventually grew violent on January 6, committee staffers said on Monday, according to CNN.
The outlet reported that Mr Cipollone was asked about his part in that meeting, in which Mr Trump included conspiratorial election deniers. The former White House counsel reportedly described the meeting as insane.
The meeting has been reported as starting as an unplanned gathering, which then fell apart as screaming matches began when General Flynn and Ms Powell started pitching their outlandish ideas about how to change the results of the election.
Committee aides told CNN Gen Flynn’s role will be discussed during Tuesday’s hearing, as well as those of other Trump allies.
The meeting that took place on 18 December 2020 is highly significant to the committee, aides said. They noted that Mr Trump tweeted the next day that his supporters should come to Washington, DC, something the panel argues led to the violence on January 6.
