By MOISES CASTILLO and ELLIOT SPAGAT
Associated Press

TIJUANA, Mexico (AP) - The Trump administration's decision to make asylum seekers wait in Mexico while their cases wind through clogged U.S. courts was made with crucial details still unknown - a move that creates uncertainty along the border and possibly an incentive for people to cross illegally before the change take effect.

The change amounts to a major shift in immigration policy, forcing thousands of asylum seekers to stay in Mexico in dangerous border cities as they navigate the American immigration court system.

On Friday, little had changed at Mexico's busiest U.S. border crossing, where Mauricio Gomez of Nicaragua joined about 150 others to learn if his name would be called to claim asylum.

"We are aware of the news, but nothing has happened so far," said Gomez, 41, who hoped to join a cousin in Nebraska. "We don't know when they are going to implement it."

Details were missing when the U.S. announced the policy Thursday in response to a large and growing number of Central American asylum seekers, many of them families, who are typically released in the United States while their cases are adjudicated, a process that can take years. The process at the border remains status quo until specific new procedures are put in place.

Homeland Security Secretary Kirstjen Nielsen said that the next step was "more legal paperwork" with Mexico.

"So, we'll work on a technical agreement with them, but we have our teams working on that now," she told Fox News on Friday.

The U.S. characterized the policy as a unilateral move, but Mexico almost simultaneously said it would grant foreigners permission to stay in the country while their asylum claims are considered in the U.S. and that they could seek work authorization. The two governments have been in discussions for months and the timing of the twin announcements suggested a high level of cooperation and coordination.

A Homeland Security official, speaking to reporters Thursday on condition of anonymity, said some details were expected in the coming days and that the policy would be rolled out in phases at different locations on the border. The U.S. said the policy will not apply to children traveling alone or to Mexican asylum seekers.

The mechanics may be complicated: Where will immigration hearings be held and how will asylum seekers get there? How will they communicate with attorneys? How will they be returned to Mexico?

Details about implementation and "the circumstances in which people will be shuttled back and forth across the border are not at all clear," said Alan Bersin, a former Customs and Border Protection commissioner who helped negotiate repatriation agreements with Mexico as a senior Homeland Security official under President Barack Obama.

Government protocols are meant to establish uniform guidelines "rather than leave it up to the operators in the field to make it up as they go along," Bersin said.

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Associated Press Writer Colleen Long in Washington contributed to this report.

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