Two senior Trump administration officials who briefed reporters at the White House said Trump will also use the “buy American and hire American” order to seek changes in government procurement practices to increase the purchase of American products in federal contracts.

Trump is to sign the order when he visits the world headquarters of Snap-On (SNA), a tool manufacturer in Kenosha, Wisconsin.

The order is an attempt by Trump to carry out his “America First” campaign pledges to reform U.S. immigration policies and encourage purchases of American products. As he nears the 100-day benchmark of his presidency, Trump has no major legislative achievements to tout but has used executive orders to seek regulatory changes to help the U.S. economy.

The order he will sign on Tuesday will call for “the strict enforcement of all laws governing entry into the United States of labor from abroad for the stated purpose of creating higher wages and higher employment rates for workers in the United States,” one of the senior officials said.

It will call on the departments of Labor, Justice, Homeland Security and State to take action to crack down on what the official called “fraud and abuse” in the U.S. immigration system to protect American workers.

The order will call on those four federal departments to propose reforms to ensure H-1B visas are awarded to the most skilled or highest paid applicant.

H-1B visas are intended for foreign nationals in “specialty” occupations that generally require higher education, which according to U.S. Citizenship and Immigration Services (USCIS) includes, but is not limited to, scientists, engineers or computer programmers. The government uses a lottery to award 65,000 visas every year and randomly distributes another 20,000 to graduate student workers.

The number of applications for H-1B visas fell to 199,000 this year from 236,000 in 2016, according U.S. Citizenship and Immigration Services.

For more on Trump’s proposed changes to the visa program, watch Fortune’s video:

Companies say they use visas to recruit top talent. More than 15% of Facebook’s (FB) U.S. employees in 2016 used a temporary work visa, according to a Reuters analysis of U.S. Labor Department filings.

But a majority of the visas are awarded to outsourcing firms, sparking criticism by skeptics who say those firms use the visas to fill lower-level information technology jobs. Critics also say the lottery system benefits outsourcing firms that flood the system with mass applications.

The senior official said the end result of how the system currently works is that foreign workers are often brought in at less pay to replace American workers, “violating the principle of the program.”

Senate Republican leader Mitch McConnell, Democratic Senator Dick Durbin of Illinois, Republican Representative Darrell Issa of California and Democratic Representative Zoe Lofgren of California were not immediately available to comment.

Facebook, Microsoft (MSFT) and Apple (AAPL) were also not immediately available after normal business hours.

The order also asks federal agencies to look at how to get rid of loopholes in the government procurement process.

Specifically, the review will take into account whether waivers in free-trade agreements are leading to unfair trade by allowing foreign companies to undercut American companies in the global government procurement market.

“If it turns out America is a net loser because of those free-trade agreement waivers, which apply to almost 60 countries, these waivers may be promptly renegotiated or revoked,” the second official said.