President Donald Trump closed the U.S.-Mexico border to all nonessential traffic, a move he said will help slow the spread of the coronavirus responsible for the COVID-19 pandemic.

Fridays announcement followed a similar move on the U.S.-Canada border, where a temporary closure is expected to go into effect Friday at midnight .

As we did with Canada, were also working with Mexico to implement new rules to suspend nonessential travel, Trump said at a press conference Friday morning. He added that the new rules will not impede lawful trade and commerce.

Trump framed the decision around his long-time desire to close down the border with Mexico, which hes attempted to do through a wall, restrictions on access to asylum, family separations, policies that send asylum-seekers back to Mexico and other initiatives.

He said unauthorized immigration has long been an issue. Weve had this problem for decades ... but now with the national emergencies and all of the other things that weve declared we can actually do something about it. Were taking a very strong hold of that. We have before, but this is now at a level that nobody has ever approached.

Similar to the Canadian agreement , trade and commercial routes are expected to remain open. Essential workers would still be allowed to cross, but travelers whose main purpose was recreation and tourism would not.

Trump has repeatedly suggested that border closures and travel restrictions will keep COVID-19 from spreading in the U.S. At this point in the nations slow coronavirus response, however, its likely that U.S. citizens are actually spreading the infection to other countries.

On Monday, Canadian health officials noted that half of Ontarios newest COVID-19 cases could be traced back to travel in the U.S.

Elise Foley contributed reporting.

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