A person familiar with the matter told NBC News that Pat Cipollone will testify on Friday before the House select committee.
Cipollone was subpoenaed last week by the panel, which said it had obtained evidence that he had raised legal and other concerns about President Trump.
Cipollone is expected to meet with the committee under a subpoena.
The spokesman for the select committee did not reply immediately.
Cipollone, who was at the White House for key moments before and during the riot, was asked to cooperate by the committee.
The vice chair of the committee said last month that Trump doesn't want Cipollone to testify because he tried to do what was right.
The initial findings from the committee's yearlong investigation into the riot at the U.S Capitol by a violent mob of Trump's supporters were laid out during one of the committee's public hearings.
There will be a public hearing on July 12 at 10 a.m. There is an hour and a half later.
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