Port of Entry in San Ysidro, California. On Jan. 25, the United States announced it will return 20 asylum seekers to wait in Mexico while their claim is processed, initiating new protocols. Photo by Ariana Drehsler/UPI | License Photo

MEXICO CITY, Jan. 25 (UPI) -- The United States will return 20 Central American asylum seekers to Tijuana through the San Ysidro, Calif., port of entry in the next few days.

"The Central Americans entered the United States through Mexican territory, and it appears they have humanitarian visas issued by Mexico, permitting multiple entries and exits from Mexico," Roberto Velasco, spokesman for Mexico's Foreign Ministry, said Friday.


The migrants' return marks the implementation of U.S. President Donald Trump's "remain in Mexico" policy, announced in December. It is the biggest modification of the asylum system in a generation.

Mexican President Andrés Manuel López Obrador called the new policy an "imposition" at his daily press briefing Friday and deferred questions to a press conference at Mexico's Interior Ministry.

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Under the new practice, asylum seekers arriving from Mexico will present their claim to U.S. authorities and be forced to wait in Mexico while their case is processed. Currently, the San Ysidro port of entry processes 60 to 80 asylum seekers a day, said Stephanie Leutert, director of the Mexican Security Initiative at the Strauss Center at the University of Texas at Austin and an expert on Mexico-U.S. immigration policies.

Mexico's government learned about the new "Migrant Protection Protocols," which were released Thursday, from the U.S. Embassy in Mexico City.

"Mexico does not agree with this unilateral decision implemented by the United States," Velasco said. "However, in accordance with our new approach to migration policy, we restate our commitment to migrants and human rights."

Homeland Security Secretary Kirstjen Nielsen said the new policy applies to "aliens arriving in the U.S. on land from Mexico," including those apprehended along the border.

The protocols do not apply to unaccompanied minors, people with health conditions or other vulnerable people. But there has been lack of clarity about what types of asylum seekers the United States would return to Mexico, raising questions about the extent of cooperation between the two countries.

"If there are returns of families," Velasco said, "that issue will have to be considered separately."

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"The Mexican government hasn't set up any protocols for the legal status of people who are returned, housing arrangements, etc., etc.," said Kennji Kizawa, senior researcher and policy analyst at Refugee Protection for Human Rights First.

"But at the same time, Mexico is under no obligation to accept the return of third state nationals. They could refuse to accept Central Americans the U.S. government tries to return. They are just claiming not to agree with this protocol but they obviously have because in order to return people they have to have the agreement of the Mexican Migration Institute to deport them," Kizawa said.

Mexico reiterated its refusal to agree to a "third safe country" agreement long sought by the Trump administration. Velasco said such an agreement would force the Mexican government to accept asylum claims by migrants returned by the United States -- which it would not do.

Even so, the rejection of the "safe third country" agreement does not mean Mexico is not cooperating with the implementation of the "remain in Mexico" policy, said Andrew Selee, president of the Migration Policy Institute, a non-partisan research organization in Washington, D.C.

"Mexico has clearly agreed to voluntarily take back Central American asylum seekers from U.S. authorities," Selee said, "but it sounds like there is still some lack of clarity about how far this cooperation will go in the future and how many non-Mexicans the Mexican government will eventually agree to take."

Velasco said the U.S. and Mexican governments have held three "technical cooperation" meetings to figure out the complexities over the past month.

U.S. authorities informed the Mexican government that the 20 people to be returned in San Ysidro are the beginning of a policy that will be rolled out along the entire border.

In announcing the new policy, Nielsen said that during October, November and December, some 2,000 "illegal and inadmissible aliens" crossed the border each day at the southern border.