The White House isn't trying to stop the publication of former national security adviser John Bolton's tell-all book, in which he reportedly claims President Donald Trump told him about plans to delay military funding to Ukraine unless investigations were done into former Vice President Joe Biden and his son Hunter, deputy White House press secretary Hogan Gidley said Thursday.

However, he told Fox News' "America's Newsroom" the National Security Council found "top-secret information" in the manuscript that must be addressed.

"In fact, the last sentence of the letter that the NSC sent to Ambassador Bolton's attorney said we are happy to work together so the book can be published," said Gidley. "According to that letter, the NSC has found top-secret information in that book. We don't want to risk the lives of American citizens. Our assets overseas. Not to mention put our brave men and women in harm's way by getting out information that would reveal sources and methods, for example. So these types of things are monitored at the career level. This isn't a political decision. It's very commonplace."

However, he said that he's not aware of an effort to stop the book's publication.

"If the ambassador wants to write a book, we have a responsibility, quite frankly, to the American people and our citizens abroad to protect them in every way possible," said Gidley, referencing Bolton's former post as U.S. ambassador to the United Nations.

Gidley on Thursday also talked about the ongoing impeachment trial, saying he is confident Trump will be acquitted despite the House's push to keep out Republican witnesses during the inquiry hearings.

Meanwhile, if Democrats want a full-blown trial with witnesses, "they better be prepared for it ... there are no facts that imply the president has done anything wrong," Gidley said. "No criminal charges in those articles of impeachment, or something in between. We are ready regardless because the facts are on our side."

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