President Donald Trump’s administration is preparing a new travel rule that could force Canadians planning to stay in the country for more than 30 days to register their information with the United States government and submit to fingerprinting.

The draft rule, which is set to take effect April 11, expands requirements for registration and fingerprinting of foreign nationals who cross the U.S.-Canada land border and stay in the U.S. longer for more than a month. Affected people would have to create an account with U.S. Citizenship and Immigration Services and schedule an appointment for fingerprinting as part of a background check.

The change could impact scores of Canadian snowbirds — retirees who spend winter months in warmer U.S. states — who may now need to either register with the U.S. government or face penalties.

Other forms, including a common I-94 travel document, are accepted in lieu of the registration, according to the notice. That document is routinely issued to non-immigrant visitors to the U.S. who arrive by air or sea.

The move comes as Trump looks to crack down on migration and as he stokes a spiralling trade war with Canada. He’s threatened widespread tariffs on Canada, and on Tuesday moved to double forthcoming steel and aluminum levies on the country. Canada is the top source of U.S. aluminum imports.

It’s unclear if the post to the Federal Register was meant as an additional provocation in that dispute. The Department of Homeland Security announced last month their plans to “fully enforce” the Immigration and Nationality Act as part of a push to “track illegal aliens and compel them to leave the country voluntarily.”

That law, which has not previously been fully enforced, mandates that noncitizens over 14 years old must register and be fingerprinted within 30 days of entry and that all registered noncitizens over 18 years old must carry proof of registration at all times. Trump issued an executive order on his first day in office directing DHS to ensure that undocumented individuals register with the government pursuant to the law.

“The Trump administration will enforce all our immigration laws—we will not pick and choose which laws we will enforce,” DHS spokesperson Tricia McLaughlin said in a February statement. “We must know who is in our country for the safety and security of our homeland and all Americans.”

DHS and the White House did not immediately comment about the push on Canadian registration.

Under the updated rule, those arriving from Canada by land, remaining in the U.S. for a month, and not otherwise registered with the federal government will be required to fill out a biographic information form, which requires phone number, date of birth, address, family information, criminal records and immigration history.

Bloomberg.com