Mexico and the U.S. announced plans Friday to sharply limit travel over their busy shared border as part of efforts to control the spread of the coronavirus.

President Donald Trump and Mexican Foreign Secretary Marcelo Ebrard said the two governments agreed to prohibit recreational and tourist travel, similar to the restrictions put in place earlier this week along the U.S. and Canadian border.

Trump said the actions with the country’s North American partners “will save countless lives.”

There would be no ban on people traveling for work or other essential activities and there would be no halt to commercial traffic, Ebrard said.

“Everyone else is not expected to have any difficulties,” he said. “We’re not talking about closing it.”

Secretary of State Mike Pompeo said the restrictions would take effect at midnight Friday.

The U.S., Mexico and Canada have also worked out a new agreement to immediately return people trying to illegally cross the borders, citing the potential health risk of detaining migrants amid the outbreak.

By excluding commercial traffic from the ban, the two governments substantially softened the economic effects. Fewer Americans are also heading south because of a statewide stay-at-home order in California and a State Department warning advising Americans not to travel abroad.

Still, the restrictions are a major development along the world’s most heavily crossed border.

Acting U.S. Homeland Security Secretary Chad Wolf told reporters at the White House that the restrictions were aimed at eliminating non-essential travel across that border.

“We want to make sure that cargo continues, trade continues, heath care workers continue to be able to traverse that border. But tourism, some recreational activities and other things needs to stop during this crisis,” he said.

U.S. officials have in recent days described plans to immediately turn back to Mexico anyone who crosses the border illegally, including asylum-seekers, under a law aimed at curbing the spread of communicable diseases.

The measure announced Friday would cover migrants crossing illegally into the United States as well as into Canada, where some people have fled to escape U.S. enforcement efforts. Ebrard said Mexico would only accept the return of migrants from Central America and Mexico, and it was not immediately clear what would happen to people from other countries.

U.S. Customs and Border Protection officials briefed business leaders Thursday on the plans to prohibit non-essential travel with Mexico, said Paola Avila, chair of the Border Trade Alliance, a business group.

U.S. officials provided a long list of “essential” workers that would be unaffected going to and from their jobs, including farm workers, restaurant and grocery store employees and bus drivers, said Avila. Mexico was preparing similar restrictions on visitors from the United States.

Keeping trade flowing, as the U.S. and Canada agreed to do, contains the economic damage. Mexico is the U.S.’s largest trading partner, just ahead of Canada. The U.S. accounts for about 75% of Mexican exports, including autos, computers and medical devices.

While halting travel for students, shoppers, families and many workers would be a major blow to border economies, the impact has already been felt.

The State Department on Thursday issued a new travel alert urging Americans not to go abroad under any circumstances and to return home if they are already abroad unless they plan to remain overseas. California Gov. Gavin Newsom ordered the state’s 40 million residents to stay at home, restricting nonessential movements.

“People are not crossing anyway,” said Avila, who is also the San Diego Regional Chamber of Commerce vice president for international business affairs. This is the right thing to do. If you don’t have to cross, don’t.”

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