The former national security does not believe that his manuscript contains any sensitive material.
In a letter to former national security adviser John Bolton's attorney, the White House said Bolton's upcoming book contains classified information that must be removed before it can be published.
In the letter to the lawyer, Charles Cooper, dated Jan. 23, a National Security Council aide wrote: "Based on our preliminary review, the manuscript appears to contain significant amounts of classified information. It also appears that some of this classified information is at the top-secret level."
"The manuscript may not be published or otherwise disclosed without the deletion of this classified information," added Ellen Knight, NSC senior director for records, access and information security management.
That letter was written days before The New York Times reported that according to a manuscript of Bolton's book, President Donald Trump told Bolton in August that nearly $400 million in aid to Ukraine would not be released until the country provided all of the information it had in connection to investigations into Democrats the president had sought. The manuscript has not been seen by NBC News.
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That reported conversation between the two men contradicts the president's impeachment defense, as Trump and his allies have said the hold on military aid and investigations were not linked. Trump said he "NEVER" had such a conversation with Bolton.
Cooper had submitted Bolton's manuscript to the NSC last month for a routine security review "notwithstanding our firm belief that the manuscript contained no information that could reasonably be considered classified."
The release of the White House response, obtained by NBC News, comes as Trump is publicly bashing Bolton over his reported claims. Earlier Wednesday, Trump asked: "Why didn't John Bolton complain about this 'nonsense' a long time ago, when he was very publicly terminated."
Calls for Bolton's testimony in Trump's impeachment trial have ratcheted up since The Times reported on the manuscript.