Late Thursday night, Donald Trump asked aides if it was too late for him to back out of his decision to make Indiana Gov. Mike Pence his vice presidential running mate, according to reporters at CNN and NBC News.

Scoop: @realDonaldTrump was so unsure about @mike_pence that around midnight last night he asked top aides if he could get out of it — Dana Bash (@DanaBashCNN) July 15, 2016

Sources tell me @realDonaldTrump was on phone till midnight making calls, asking if he could change course on VP pick — Kelly O’Donnell (@KellyO) July 15, 2016

On air on MSNBC Friday afternoon, O’Donnell said that sources told her that Trump was unsure of his choice for vice president and was looking for a way to back out of the decision.

News leaked on Thursday afternoon that Trump would select Pence to be his running mate. Then, after the attack in Nice, France, the Trump campaign cancelled Trump’s Friday morning even to announce his vice presidential pick. Trump subsequently went on Fox News and said that he had not made a “final, final decision,” casting doubt that he had decided on Pence.