The Trump administration has shut down an Obama-era loophole that let immigrants who otherwise could not legally enter the U.S. claim a free pass by saying they were “entrepreneurs.”

The U.S. Citizenship and Immigration Services, part of the Department of Homeland Security, announced an end to the program, claiming former President Barack Obama overstepped his powers in creating it.

The administration also said that the program that let immigrant small businessmen and women enter was a threat to U.S. workers, a key focus of the White House.

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In a statement, Homeland Security said that “the department believes that it represents an overly broad interpretation of parole authority, lacks sufficient protections for U.S. workers and investors, and is not the appropriate vehicle for attracting and retaining international entrepreneurs.”

It is not clear how many immigrants came in through the loophole.

The administration said in closing it that there are many other ways for investors and entrepreneurs to enter the U.S. legally and, if needed, Congress could offer new legislation to address the issue.

While those let in under Obama might have felt their immigration status was open-ended, the Trump administration said it is not and at the end of their “temporary” status the immigrants will be required to return home.

The temporary status, said the administration, undermined the value of the businesses created by the immigrants. DHS said the program “focused too narrowly on the economic benefits that potential foreign entrepreneurs may bring, without giving sufficient attention to the existing statutory scheme and the absence of a durable immigration status for these individuals, which is not made available through the device of temporary parole.”

It is the latest example of the Trump administration moving to close many of the Obama-era immigration expansion programs.