The comments, trailed early Tuesday ahead of the interview being broadcast later this week, came as the administration hardens its already extreme line on immigration ahead of the midterm elections next month. "It was always told to me that you needed a constitutional amendment", he told Axios.
Can Trump get rid of birthright citizenship through an executive order?
Leaving the White House on Wednesday for a Florida rally, Mr Trump kept the focus on immigration, telling reporters the U.S. could send as many as 15,000 military troops to the border with Mexico. In an interview with Axios that aired Tuesday morning, the president declared he will end the right in the 14th Amendment via executive order, and claims the Constitution does not cover birthright citizenship. Responding to critics on Wednesday, he said that birthright citizenship will be abolished "one way or another".
Trump said he had spoken to legal counsel about it and that the change is in the works. "Guess what? You don't", Trump said.
The legal argument espoused by conservative activists for excluding children of illegal immigrants would likely be based around the language in the 14th Amendment that says people born in the United States are citizens if they are "subject to the jurisdiction" of the United States.
Trump's remarks mark another escalation in his hardline stance on immigration ahead of U.S. midterm elections on November 6 that could see the Democrats regain some degree of power. We don't even know how many of these kids don't make it and may have been waylaid into sex trafficking or killed because they fell off a train.
Trump claimed that the USA was unique in granting birthright citizenship.
"This is simply an attempt for Donald Trump, who wants to do anything possible to bring back fears around immigration, to use that as a political tool in this last week before the election", Warner said. He called it "outrageous that the president can think he can override constitutional guarantees by issuing an executive order".
Several other countries, including Canada, have a policy of birthright citizenship, according to an analysis by the Center for Immigration Studies, which advocates for reducing immigration.
On Wednesday, Mr Trump took to Twitter to vent his ire at the most powerful congressional Republican.
John Eastman, a constitutional scholar at Chapman University's Center for Constitutional Jurisprudence, told Axios that the line "subject to the jurisdiction thereof" originally referred to people fully and politically allied with the U.S. - green-card holders and citizens. "But the Supreme Court of the United States has never ruled on whether or not - whether the language of the 14th Amendment, 'subject to the jurisdiction thereof, ' applies specifically to the people who are in the country illegally", he said at a Politico event.
Whether or not birthright citizenship is within the president's power to change is a subject of debate among constitutional scholars. "If you are born in this country, you are an American".