The White House sent a formal letter to former National Security Adviser John Bolton amid furor about his upcoming book, warning parts with classified information may not be published, media reports said Wednesday.

In the Jan. 23 letter to Bolton’s lawyer, Director for Access Management at the National Security Council Ellen Knight said, The Room Where It Happened: A White House Memoir, “appears to contain significant amounts of classified information.”

“Under federal law and the nondisclosure agreements your client signed as a condition for gaining access to classified information, the manuscript may not be published or otherwise disclosed without

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