Trump's National Security spokesman to leave White House

"Michael is one of the smartest and most talented individuals I've ever worked with -- not to mention an amazing chef," Sanders said Sunday.

"He has been more than a colleague, he is a true friend. Every day I got to work with Michael was a good day, and he will be greatly missed."

Anton's departure comes amid a series of changes at the National Security Council, including former US Ambassador to the UN John Bolton taking the helm on Monday after H.R. McMaster stepped down as Trump's top National Security Adviser (NSA), reports CNN.

Anton was brought into the NSC by Michael Flynn, Trump's first NSA, who plead guilty to lying to the Federal Bureau of Investigation (FBI) last year.

Trump called Anton on Sunday and thanked him for his service, a White House official said.

"He said he is a great guy and we will all miss him," the official added.

According to sources, Anton was well liked by his White House colleagues and known as the rare conservative intellectual that joined Trump's administration, reports CNN Months before the 2016 election, Anton -- reportedly writing under the name Publius Decius Mus -- wrote "The Flight 93 Election", an article that praised Trump's campaign and argued that a Clinton presidency "is Russian Roulette with a semi-auto".

"With Trump," he wrote, "at least you can spin the cylinder and take your chances."