House Speaker Paul Ryan said Thursday that he would sue Donald Trump if the presumptive Republican nominee tried to unilaterally implement an indefinite ban on Muslim immigration.
In an interview with The Huffington Post, published Friday, the Wisconsin Republican said he'd "sue any president that exceeds his or her powers."
Ryan, who said Trump supported the separation of powers when the speaker endorsed him, released part of his agenda regarding executive overreach this week.
However, Ryan conceded he was not entirely sure if it was outside the president's authority to enact a ban on Muslim immigration.
"That's a legal question that there's a good debate about," Ryan said, referencing the 1952 Immigration and Nationality Act.
On Monday, Trump said that he would have the legal authority to do so as president.
"The immigration laws of the United States give the president powers to suspend entry into the country of any class of persons," he said at a rally. "I will suspend immigration from areas of the world where there is a proven history of terrorism against the United States, Europe or our allies, until we fully understand how to end these threats."
Trump's campaign did not immediately respond to a request for comment from Business Insider.
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