EL PASO, Texas (Reuters) - Workers and students who frequently cross the U.S. border with Mexico worried over the weekend about the impact on their lives if President Donald Trump follows through on a threat to shut entry points used by hundreds of thousands of people every day.

Faced with a surge of asylum seekers from Central American countries who travel through Mexico, Trump said on Friday there was a “good likelihood” he would close the border this coming week if Mexico does not stop unauthorized immigrants from reaching the United States.

Shutting the southern frontier completely would disrupt billions of dollars in trade and millions of legal border crossings, including those made by U.S. citizen Andrea Torres.

The 22-year-old student spends weekdays with her aunt in El Paso, where she attends the local campus of the University of Texas, and weekends with her mother in Ciudad Juarez, Mexico.

On the border bridge linking the two cities, so many students cross every day that authorities have assigned them their own pedestrian lane.

“Right now, it’s better for me to stay in El Paso because I need to finish school,” Torres, who is studying art history, said on Friday as she headed to Juarez for the weekend.

That would mean missing her mom. “It would be really hard,” Torres said. “I’m really close to her.”

Slideshow ( 5 images )

Gerardo Pozas, a 38-year-old mechanic, moved to El Paso from Juarez in 1997 to attend high school and later became a U.S. citizen. He has always retained strong ties with his birthplace. He worried what he would do if Trump closed the border.

“My family, my church and my girlfriend are (in Juarez). I wouldn’t be able to go,” Pozas said. “But if I stay there, in Ciudad Juarez, I wouldn’t be able to come to my house.”

LONG LINES AT BORDER

Department of Homeland Security officials had already warned traffic with Mexico could slow as the agency shifts personnel from ports of entry to help process asylum seekers.

Delays were already being felt on Friday, with waiting times longer than usual on the Mexican side of the crossing between Juarez and El Paso, and hours-long lines for trucks carrying goods from Mexican factories into the United States.

Trade between the United States and its third-largest trading partner totaled $612 billion last year, according to the U.S. Census Bureau.

Slideshow ( 5 images )

Brandon Carlan, a 21-year-old waiter from Boston, Massachusetts, works in San Diego but lives in Tijuana, Mexico, because he cannot afford San Diego’s high rents. He said he crosses the border every day.

“(Closing it) would affect me economically because I wouldn’t be able to pay for my bills,” Carlan said. “There are people going back and forth every day and they are not going to be able to see their families or go to their houses.”

Construction worker Alejandro Villegas, 43, is from Tijuana, Mexico, but lives in San Diego. He said many of his colleagues live in Mexico and cross the border daily.

“People have kids who study on this side and on the Mexican side and they have to cross to take them to school, to go shopping and to work so this is a big problem for us,” he said.

Trump, who launched his presidential campaign in 2015 with a promise to crack down on illegal immigration, has repeatedly threatened to close the border during his two years in office but has not followed through.

Mexico has played down the possibility of a border shutdown. On Friday its foreign minister, Marcelo Ebrard, said the country does not act on the basis of threats.

(Graphic: Trump threatens to shut U.S.-Mexico border - tmsnrt.rs/2V59n2R)