By Suzanne Monyak

Law360 (March 18, 2020, 2:10 PM EDT) -- The Trump administration plans to turn away migrants and asylum-seekers at the southwest border under a law that allows the U.S. to block foreigners from entering the U.S. in an effort to stop the spread of the new coronavirus.

President Donald Trump said at a Wednesday press conference that he plans to invoke a law known as 42 U.S. Code Section 265, which allows the president to suspend the entry of people and imports into the U.S. when it is "required in the interest of the public health."

When asked if he plans to draw on the statute to block asylum-seekers and people without papers at the southern border, Trump said, "The answer is yes."

He also said his administration would announce the border restrictions "very soon, probably today."

Also Wednesday, the White House announced that the U.S. and Canada had agreed to close their shared border to nonessential travel over concerns about the spread of the virus. Trade over the border will not be affected.

"It was through mutual discussion that took place this morning between the president and Prime Minister [Justin] Trudeau, and the Department of Homeland Security will be effectuating that decision," said Vice President Mike Pence, who is leading the White House's coronavirus task force.

Representatives for the U.S. Department of Homeland Security and White House didn't respond to a request for more details on the plans.

Sarah Pierce, an immigration attorney and policy analyst with the nonpartisan Migration Policy Institute, said she couldn't recall a time this statute, which was placed on the books in 1944, had been used before.

"This is just completely unchartered waters," she told Law360 on Wednesday.

She also said that people on nonimmigrant visas, asylum seekers, and green card holders entering the U.S. for the first time could theoretically be vulnerable to the restrictions.

The new coronavirus, which causes the illness COVID-19, has spread to all 50 U.S. states, as well as the District of Columbia, Puerto Rico, Guam and U.S. Virgin Islands, according to the Centers for Disease Control and Prevention.

More than 7,000 people in the U.S. have tested positive for the disease, according to the most recent CDC data.

As of a March 17 report by the World Health Organization, there are 53 confirmed cases of COVID-19 in Mexico and 424 confirmed cases in Canada.

The border restrictions would mark one of several strict measures the U.S. has implemented in an attempt to mitigate the spread of the novel coronavirus.

The U.S. has blocked foreigners who have spent time recently in the United Kingdom, Ireland, China, Iran and the 26 European countries that comprise the Schengen free travel zone from entering the U.S., with exceptions for U.S. green card holders.

Americans and green card holders returning to the U.S. from those areas are now filtered through 13 airports, where they are given medical screenings, and quarantined if necessary.

The restrictions are also among several implemented by the Trump administration to cut back on asylum claims at the U.S.-Mexico border, including by stripping asylum eligibility from those who passed through another country on the way to the U.S., pushing asylum applicants back to Mexico to await their U.S. immigration court dates, and sending some asylum-seekers to Guatemala instead under a bilateral accord.

The Trump administration had also attempted to block migrants who entered the U.S. outside of designated entry ports, but that immigration rule has been blocked by the federal courts while a lawsuit challenging the restrictions continues.

--Editing by Marygrace Murphy.

Update: This story has been updated with a comment from a policy analyst for the Migration Policy Institute.

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