On Monday, Leon Panetta suggested that Trump offer Obama an apology for the wiretapping allegations and "move on."
The former CIA Director and Defense Secretary offered the advice during an appearance on MSNBC's 'Morning Joe.'
He said, "I don't think there is any evidence here. The president frankly ought to acknowledge that a mistake was made, apologize to President Obama and move on...He's got too many other issues to deal with."
The apparent lack of proof has prompted a growing number of politicians from both parties to suggest it's time for Trump to back down from the claim and acknowledge he was wrong, notes the Huffington Post.
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On Friday, Republican Representative Will Hurd of Texas told ABC's 'This Week,' "To quote my 85-year-old father...who has given this advice to all of my friends when they get married, it never hurts to say you're sorry."
Oklahoma's Representative Tom Cole said, "I see no indication that that's true...And frankly, unless you can produce some pretty compelling proof, then I think that President Obama is owed an apology in that regard."
That same day Representative Charlie Dent of Pennsylvania called Trump's claim, "inexplicable," notes CNN.
Nonetheless, White House press secretary Sean Spicer has noted of Trump and his wiretapping assertion, "He stands by it," and said of the Senate Intelligence Committee, "They have yet to go through the information."