President Donald Trump ripped into House Speaker Paul Ryan (R-WI) Wednesday for contradicting him on his ability to scrap birthright citizenship.

Paul Ryan should be focusing on holding the Majority rather than giving his opinions on Birthright Citizenship, something he knows nothing about! Our new Republican Majority will work on this, Closing the Immigration Loopholes and Securing our Border! — Donald J. Trump (@realDonaldTrump) October 31, 2018

Ryan has been reluctant to criticize the President harshly, but said explicitly to a local radio station Tuesday that Trump’s notion that he can nullify birthright citizenship, a right enshrined in the 14th Amendment, by executive order is unconstitutional.