Story highlights "I believe that is very likely that that takes place sometime in the next few days," Sanders said

Comey's firing Tuesday night sent shockwaves through the FBI

(CNN) A White House spokeswoman said Thursday that former FBI Director James Comey directly relayed information about the Russia investigation to President Donald Trump.

Sarah Huckabee Sanders was asked on ABC's "Good Morning America" about Trump's claim in a letter to Comey notifying him of his termination that the then-FBI director assured him "on three separate occasions" that he was not under investigation.

"Are you sure that what the President wrote is true?" asked host George Stephanopoulos.

"I have heard that directly from him that information was relayed directly to him from Director Comey," said Sanders, who declined to provide further details.

The White House has so far declined to produce evidence of the three separate occasions the President referenced.

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