FILE - In this March 5, 2019, file photo, Ruth Aracely Monroy walks with her sons in Tijuana, Mexico. After requesting asylum in the United States, the family was returned to Tijuana to wait for their hearing in San Diego. The Trump Administration appealed a San Francisco judge's ruling Wednesday, April 10, 2019, that would block it from returning asylum seekers to Mexico to await court hearings. (AP Photo/Gregory Bull, File)

SAN FRANCISCO - The Trump administration on Wednesday appealed a judge's ruling that would block the government from returning asylum seekers to Mexico to await court hearings.

The one-sentence appeal filed in the 9th U.S. Circuit Court of Appeals did not immediately ask to stop the lower court ruling from going into effect Friday.

Judge Richard Seeborg has given the government until the end of the week to ask for a stay of Monday's ruling, in which he granted a request by civil liberties groups to halt the practice while their lawsuit moves forward.

The administration's policy violated U.S. law by failing to adequately evaluate dangers migrants face in Mexico, Seeborg said. He said a law cited by government officials did not apply to the 11 asylum seekers who sued.

The U.S. took the unprecedented action at the nation's busiest border crossing — in San Diego — in response to growing numbers of families fleeing poverty and gang violence in Guatemala, Honduras and El Salvador.

About 1,000 migrants have been sent back to Mexico since the policy went into effect in January and was later expanded across the California border and to West Texas.

Families seeking asylum that typically would have been released in the U.S. with notices to appear in court were instead sent back to Mexico to await their hearings.

The administration had hoped the move would discourage weak asylum claims and help reduce an immigration court backlog of more than 800,000 cases.

Under the new policy, asylum seekers were not guaranteed interpreters or lawyers and couldn't argue to a judge that they face the potential of persecution or torture in Mexico, the American Civil Liberties Union argued.

The San Francisco ruling came up Wednesday at a case in El Paso, Texas, where lawyers for a Salvadoran man who said he had been threatened in Mexico asked for permission to stay in the U.S. while his case proceeds.

A Homeland Security attorney assured the judge that the man would not be sent back to Mexico, even though the California court decision doesn't take effect until Friday.

President Donald Trump had criticized the ruling as unfair. His administration has said it's trying to cope with a crisis at the southern border.

While Border Patrol arrests, the most widely used gauge of illegal crossings, have risen sharply over the last year, they are relatively low in historical terms after hitting a 46-year low in 2017.

News from © The Associated Press, 2019