WASHINGTON—The Department of Homeland Security said Monday it would make 15,000 more visas available for seasonal workers, increasing by nearly 50% the number of foreigners able to work in the U.S. this summer.

The decision responds to complaints from businesses and members of Congress about a significant shortfall in H-2B visas that left hotels, restaurants and other businesses that see a surge of demand in the summer scrambling.

Administration officials said last month that they would issue more visas but didn’t say how many or when applications would be accepted. On Monday, officials said that applications would be accepted beginning Wednesday, and that 15,000 would be available.

To qualify, employers must attest that their businesses are likely to suffer “irreparable harm,” defined as permanent and severe financial loss, without the H-2B workers.

While some U.S. lawmakers sought even more visas, DHS officials said this amount would cover the number of companies that meet this criteria.

Businesses seeking additional visas can expect to wait 30 to 60 days for the petitions to be approved, senior DHS officials said. The officials encouraged companies to seek “premium processing” for their petitions, which costs about $1,200 but can shorten the wait time to about two weeks.

Legislation authorizing the additional visas wasn’t approved until the spring.

“We understand that is late in the season,” said David Lapan, a spokesman for the Department of Homeland Security. “We’re working as hard as we can.”

By law, the number of H-2B visas, which are available for temporary, nonagricultural jobs, is capped at 66,000, divided between the summer and winter seasons. This year, the summer allotment was exhausted in March.

In past years, Congress has exempted returning workers from the cap, enabling many additional foreigners to participate in the program, but lawmakers didn’t renew that exception for this year. Instead, on April 30, Congress gave DHS authority to add additional visas if Homeland Security Secretary John Kelly found businesses that were at risk without them. It took DHS until now to use the authority granted.

President Donald Trump, a Republican, built his presidential campaign on a promise to protect U.S. workers from foreign competition and regularly said U.S. interests are threatened by foreigners who come to the country both legally and illegally. As president, he has pushed a “Hire American” agenda and suggested he may try to restrict existing visa programs. Still, his own Mar-a-Lago club in Palm Beach, Fla., has used many H-2B workers for its winter season.

In a nod to concerns about unfair competition from foreign workers, DHS said it was establishing a tip line for members of the public who want to report employers they suspect are abusing the program. People who want to submit reports can email ReportH2BAbuse@uscis.dhs.gov.

Roy Beck, president of Numbers USA, an advocacy group that wants to restrict legal and illegal immigration, said he was disappointed in the decision.

“At least Kelly limited the damage to keeping just 15,000 more Americans out of the labor market,” he said. “Nonetheless, this is yet another example of the administration and Congress failing to keep the Trump campaign promise of putting American workers first.”

The H-2B Workforce Coalition, which lobbied for additional visas, saw a mixed result, too. In a statement, the coalition said it is “grateful for the minimal relief granted.”

“Though we fear this gesture may be too little too late for thousands of small businesses that rely on legal, highly vetted seasonal guest workers to meet their peak season needs, the additional visas may help save some small businesses this year,” the coalition said.