President Trump's team is tightening enforcement of the rules governing a visa program for high-skilled workers, and changing policies to protect lower-skilled workers from foreign competition.

A new policy announced Monday would allow U.S. Citizenship and Immigration Services agents to prioritize companies for site visits if they seem likely to engage in "visa fraud and abuse."

USCIS agents plan to make unannounced visits to companies that trigger visa fraud red flags, such as having "a high ratio of H-1B workers as compared to U.S. workers, as defined by statute," according to the bulletin. Companies for which basic business information cannot be validated will also be targeted.

The agency is also establishing an email that people can use to alert USCIS when they think their employer is gaming the high-skilled visa system. "Employers who abuse the H-1B visa program negatively affect U.S. workers, decreasing wages and job opportunities as they import more foreign workers," according to USCIS. "Information submitted to the email address will be used for investigations and referrals to law enforcement agencies for potential prosecution."

USCIS noted that U.S. companies should not be looking to use the H-1B program, which allows the temporary entry of workers in certain high-skilled or hard-to-fill jobs, to discriminate against U.S. workers.

"The H-1B visa program should help U.S. companies recruit highly-skilled foreign nationals when there is a shortage of qualified workers in the country. Yet, too many American workers who are as qualified, willing, and deserving to work in these fields have been ignored or unfairly disadvantaged," USCIS emphasized. "Protecting American workers by combating fraud in our employment-based immigration programs is a priority for USCIS."

That note was released on the same day that the Justice Department issued a similar warning.

"U.S. workers should not be placed in a disfavored status, and the department is wholeheartedly committed to investigating and vigorously prosecuting these claims," said a top DOJ official.

Last week, USCIS announced a new policy that will make it harder for foreign-born workers to take low-level jobs as computer programmers, in keeping with Trump's contention that U.S. immigration policies have deprived low-skilled Americans of jobs or higher wages.

Specifically, USCIS rescinded a Bill Clinton-era memo on enforcing the rules around the H-1B visa program. "[T]he fact that a person may be employed as a computer programmer and may use information technology skills and knowledge to help an enterprise achieve its goals in the course of his or her job is not sufficient to establish the position as a specialty occupation," a March 31 memo said.

Trump made abuse of the H-1B visa program a key weapon in his attack on Sen. Marco Rubio, R-Fla., during the Republican presidential primaries. He featured Disney employees who said they were laid off after training their foreign replacements at a campaign rally and used their stories to attack Rubio for working on the Gang of Eight immigration bill.

"Marco Rubio has betrayed American workers," one of the workers said in February of 2016. "I am endorsing Donald Trump because I believe he will stand up to the all powerful corporations that spend millions each month in Washington DC in an attempt to influence our lawmakers."

The executive actions give Trump a much-needed accomplishment on an issue that fueled his campaign, given how congressional Democrats standing in the way of his proposed border wall. The moves are drawing support even from Republicans who favor expanding the high-skilled visa program, such as Utah Sen. Orrin Hatch, now a prominent ally of he president.

"I support efforts to ensure the H-1B program is used for its intended purposes and look forward to working with the administration to confirm that this continues to be the case," Hatch said in a statement to the Washington Examiner.