Families that have waited years to be reunited, businesses that rely on foreign workers, universities that recruit international students with the promise of high-paying American jobs — all of their plans faced new uncertainty on Tuesday as the Trump administration announced new temporary restrictions on permanent residency in the United States.

President Trump signaled that a 60-day ban on most green cards, which could be imposed as early as Wednesday, was intended to protect work opportunities for the millions of Americans who have lost their jobs in the coronavirus pandemic. But, if it is extended, its impact on businesses and families could be much broader.

The new policy would close the doors to thousands of people hoping to enter the United States or lay down permanent roots in the country through long-term work or family connections — at least temporarily.

“It’s really worrying news,” said Elsa Ramos, whose 22-year-old son, Eder, is in Honduras, waiting for a green card that would allow him to join his parents and sister in the United States. They are among many families and employers who have spent thousands of dollars on years of legal work and are now on hold.