House GOP secures four key witnesses in Biden mental-decline probe as former aides agree to talk

Four former Biden aides have agreed to voluntarily testify in House Oversight Republican's investigation into an alleged cover-up of former President Joe Biden’s mental decline and potentially unauthorized issuance of sweeping pardons and other executive actions.

The four voluntary, transcribed interviews, confirmed today by a GOP Oversight Committee aide, will include the director of Biden's former Domestic Policy Council, Neera Tanden, Biden's assistant and senior advisor to the first lady, Anthony Bernal, former special assistant to Biden and Deputy Director of Oval Office Operations, Ashley Williams, and Biden's Deputy Chief of Staff, Annie Tomasini.

COMER WIDENS BIDEN 'COVER-UP' PROBE, SEEKS INTERVIEWS WITH ANITA DUNN AND RON KLAIN

Tanden will appear before the House Oversight Committee on June 24, Bernal two days later on June 26, while Williams will testify July 11 and Tomasini on July 18. 

Former Biden aides will be questioned over the next few weeks in Republicans' ongoing investigation into whether there was an alleged cover-up of former President Joe Biden’s mental decline. (DOJ/Getty)

News of the voluntary testimonies comes after Biden's former White House doctor, Kevin O'Connor, declined to sit for a transcribed interview on June 27, according to Oversight Committee Republicans leading the probe.

BIDEN'S PERSONAL DOCTOR SUMMONED AS REPUBLICANS DIG DEEPER INTO ALLEGED COGNITIVE DECLINE COVER-UP

House Oversight Committee Chairman James Comer, R-Ky., has subpoenaed former President Joe Biden’s physician Kevin O'Connor, seen here walkig with the president, to appear for a deposition as part of a probe into Biden's mental decline.  (Manuel Balce Ceneta/AP)

Fox News Digital reached out to the former president's office for comment, but did not hear back in time for publication. 

This is a breaking story and will be updated as new information becomes available.