FILE PHOTO: U.S. President Donald Trump delivers remarks at a campaign rally in Bossier City, LA, U.S., November 14, 2019. REUTERS/Tom Brenner/File Photo Reuters

According to the book „A Warning“ by an anonymous senior Trump administration official, President Donald Trump once considered labeling migrants „enemy combatants.“

The author said Trump floated the idea to advisers and „mused about shipping migrants to Guantanamo Bay.“

The author said advisers were „mortified,“ and quickly shut down the suggestion by saying it was impractical and too expensive.

According to an April report from The New York Times, officials from the Department of Homeland Security also once floated the same idea.

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President Donald Trump floated the idea of labeling migrants „enemy combatants“ and holding them at Guantanamo Bay, a military base known for detaining terror suspects — and the suggestion „modified“ his advisers, according to the book „A Warning“ by an anonymous senior Trump administration official.

The author, who reportedly still works in the Trump administration, wrote that Trump believed that if migrants were given „enemy combatant“ labels, he would have reason to keep them out of the country.

„It was unclear if someone had planted this in his head or whether he had come up with it on his own, but either way, advisors were mortified,“ the author wrote in „A Warning,“ which was released on Tuesday.

This isn’t the first time the idea has been mentioned. Officials from the Department of Homeland Security also considered housing migrant children at Guantanamo Bay, according to an April report from The New York Times.

The „A Warning“ author said Trump floated the idea of changing migrants‘ labels in meetings and told „random“ advisers is plan. The book said that many advisers froze up, giving him „polite smiles reserved for a deranged relative.“

„Trump went further and mused about shipping migrants to Guantanamo Bay, where hardened terrorists were jailed. In his mind, the deterrent would be a powerful one: Come to the United States illegally, and you will be sent to a remote US detention facility in Cuba to live alongside murderous criminals,“ the author said.

The suggestion riled his advisers. One State Department official called the proposal „Bats—,“ and another exclaimed „are you f—ing kidding me?“ when he was made aware of Trump’s ideas. Advisors shut Trump’s idea down „quickly and quietly“ by telling the president that it was impractical and too expensive, the author said.

The author said it was difficult to discern whether the president ever actually let the idea go. „On some days, the return of a half-baked suggestion is harmless. On other days, it would the president his office if it was carried out,“ they wrote.

The anonymous author was against the detainment of holding migrants at Guantanamo, saying: „Migrants seeing shelter in the United States are not ‚enemy combatants.‘ They are not engaged in hostilities against the United States on behalf of foreign states or terror groups, even though the president and his border agencies like to insinuate that the throngs of arriving migrants could have dangerous militants in their midst.“