Paul Ryan. AP Photo/Andy Manis Paul Ryan considers Donald Trump's proposal to indefinitely ban Muslim immigration into the US to be executive overreach.

And during an interview with The Huffington Post, uploaded on Friday, the House speaker 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 the presumptive Republican nominee, released part of his agenda regarding executive overreach this week.

However, Ryan is not totally sure if Trump enacting a ban on Muslims entering the country would be outside of presidential authority.

"That’s a legal question that there’s a good debate about," Ryan said, pointing to the 1952 Immigration and Nationality Act. That act was meant to exclude immigrants from certain countries from coming to the US in the aftermath of World War II.

On Monday, Trump made the appeal that he could legally enact such a ban 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 not yet responded to a request for comment from Business Insider