Brian Williams, the embattled NBC Nightly News anchor, will not make his scheduled appearance on The Late Show with David Letterman this week.

Brian Williams Cancels ‘Late Show’ Stop

Williams was slated to chat with longtime Late Show host David Letterman Thursday, which many thought would be a great opportunity for Williams to casually address the controversy currently surrounding his reporting. However, days after Williams announced his decision to take a temporary hiatus from Nightly News, he’s canceled his booking on the late night program, reported USA Today.

While Williams removes himself from the air, NBC is conducting an internal investigation to find out more about Williams’ erroneous story, which placed him in a helicopter that was shot down by combatant gunfire in Iraq in 2003. An Army veteran pointed out the inaccuracy of Williams’ first-hand account on Facebook, which led Williams to quickly apologize to the soldier.

According to Williams’ multiple apologies, he mistakenly conflated his true experience of traveling in a following helicopter and later hearing about the downed helicopter without actually being on the downed aircraft. Archival footage of Williams’ reports shows him telling the less dramatic version of the story in 2003, with the more dramatic retelling evolving in the years since.

Since Williams’ anecdotal reporting of his time in Iraq has come under scrutiny, as has his first-hand accounts down on the ground in New Orleans during Hurricane Katrina.