Ricardo Molina helps pass out food to residents of El Cenizo outside of the community center. (Matthew Busch/Matthew Busch For The Washington Post)

Attorney General Jeff Sessions said Friday that the Trump administration “fully supports” Texas’s harsh new ban on sanctuary cities, and the Department of Justice will help defend it against a federal court challenge next week.

Lawyers for the tiny border city of El Cenizo, the League of United Latin American Citizens and major cities such as Dallas and Austin say the law requiring them to detain immigrants for federal deportation agents is “patently unconstitutional” for a number of reasons. On Monday, they will urge U.S. District Court Judge Orlando Garcia in San Antonio to block the law from taking effect Sept. 1.

The state of Texas argues that the government is within its rights to bar localities from interfering with immigration enforcement. Under the law, officials could lose their jobs, police chiefs could go to jail, and governments could face fines of up to $25,500 a day if they adopt or enforce policies that prevent law enforcement officers from asking about a person’s immigration status or complying with requests to detain immigrants, a job that has been chiefly the responsibility of federal agents.

“President Trump has made a commitment to keep America safe and to ensure cooperation with federal immigration laws,” Sessions said in a statement. “Texas has admirably followed his lead by mandating state-wide cooperation with federal immigration laws that require the removal of illegal aliens who have committed crimes.”

Luis Roberto Vera, Jr. the national general counsel for the League of United Latin American Citizens, which is a plaintiff in the case, said the Texas law is discriminatory because it primarily targets Hispanics, one of the state’s largest groups.

El Cenizo Mayor Raul Reyes. El Cenizo is the lead plaintiff in a lawsuit that will seek to temporarily halt Texas’ sanctuary cities ban before it takes effect Sept. 1. (Matthew Busch/Matthew Busch For The Washington Post)

“It’s a continuation of Donald Trump’s war on Mexicanos,” Vera said. “That’s the sad part about this.”

The faceoff comes amid rising tensions nationwide over the Trump administration’s crackdown on immigration and its relentless march forward despite a string of losses in federal courts.

On Friday, congressional aides said House Republicans are advancing a bill that would withhold some federal grant money from so-called sanctuary cities; give greater legal weight to immigration detainers, which are requests from Immigration and Customs Enforcement to local jails to hold immigrants who are being targeted for deportation; and shield local governments from lawsuits related to detainers. A second bill would increase penalties against deported immigrants who return illegally.

Sponsor Rep. Bob Goodlatte (R-Va.) said the bills, which could be voted on as early as Wednesday, “crack down on dangerous sanctuary policies that needlessly put innocent lives at risk.”

But advocates say ICE is arresting many immigrants who do not pose a threat to public safety, such as a Falls Church woman deported to El Salvador last week. Some members of Congress have raised concerns about spending limited federal dollars to deport otherwise law-abiding immigrants, who are often parents of U.S. citizens.

Congresswoman Louise M. Slaughter (D-N.Y.) criticized the GOP-led House for “conjuring up red-meat partisan political bills — like deporting immigrants — despite the major issues facing this country at this time.”

Hundreds of local jurisdictions, from county sheriffs to major cities such as New York, have adopted sanctuary policies that limit their cooperation with ICE, the agency that detains and deports immigrants.

Protesters line the balconies of the state Capitol rotunda to protest a bill already passed by Texas Gov. Greg Abbott that compels local police to enforce federal immigration law. (Ricardo Brazziell/AP)

Sanctuary cities say aiding immigration agents deters immigrants from reporting crime and could lead to racial profiling and deportations for minor offenses. In Houston, which sought to join the El Cenizo lawsuit Friday, police noted a sharp decline in reports by Hispanics of sexual assault and violent crime in the first three months of 2017, compared to the same period last year.

Texas Gov. Greg Abbott (R) says the law would enhance public safety by ensuring that sanctuary cities turn over immigrants who have been arrested for crimes. He and others have cited cases in which immigrants have been released and reoffended.

As a candidate, Trump campaigned against sanctuary cities. On Jan. 25, days after he took office, he issued an executive order vowing to strip federal funding from those cities that refuse to enforce immigration law.

In April, a federal judge in San Francisco temporarily halted that order after the city and Santa Clara County filed a lawsuit and the Trump administration acknowledged that its crackdown was far narrower than the president and his aides had indicated.

Ten states — including Texas — have backed the Trump administration in the San Francisco case.