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President Trump announced Thursday that former U.S. Ambassador to the United Nations John Bolton will replace Gen. H.R. McMaster as National Security Adviser effective April 9.

Bolton, a Fox News contributor, joined Martha MacCallum on "The Story" to react to the president’s announcement, which comes after months of speculation about McMaster's future.

"It's obviously a great honor. It's always an honor to serve our country, and I think particularly in these times internationally," Bolton said.

MacCallum asked Bolton about Trump's congratulatory call to Russian President Vladimir Putin after winning his election on Tuesday.

Bolton said he didn't see anything wrong with the call, but he was "outraged" that a memo prepared for Trump before the call -- which warned him not to congratulate Putin -- was leaked. The memo read, “DO NOT CONGRATULATE” in all-caps.

"It recalled earlier in the administration when somebody was leaking transcripts of the president's conversations with foreign leaders. It's completely unacceptable," Bolton said. "You cannot conduct diplomacy, you cannot expect other foreign leaders to be candid and open in their conversations with the president if some munchkin in the executive branch decides they're going to leak the talking points or the transcript or any other aspect of it."

He said there should be bipartisan agreement that leaking of this sort is simply unacceptable.

Watch the full interview above, and get more on this White House shakeup on FoxNews.com.

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