Citing unemployment levels not seen since the Great Depression, U.S. Senate and House Republicans sent letters Thursday urging President Trump to "suspend" guest worker visa programs until the economy recovers or for at least one year -- whichever comes first.

"There is no reason why unemployed Americans and recent college graduates should have to compete in such a limited job market against an influx of additional H-1B workers, most of whom work in business, technology, or STEM fields," wrote Republican Senators Tom Cotton of Arkansas, Ted Cruz of Texas, Chuck Grassley of Iowa and Josh Hawley of Missouri, in their letter to Trump.

Trump's H-1B position opened the door for these two letters late last month after announcing a "pause" on immigration in the U.S. He excluded H-1B workers from his initial executive order pending a report by his administration on ways to "prioritize Americans."

The letters, along with a new study on H-1B wage levels, may renew fierce debate over the future of the H-1B visa program. The wage study by the Economic Policy Institute (EPI), a think tank based in Washington, D.C., argues that the government is allowing employers to undercut U.S. workers on pay.

House lawmakers referenced the visa pay issue in their letter: "The workers enrolled in these programs hold no unique skills relative to those held by American college graduates, but the cost of their services is significantly less," wrote Republican House members Lance Gooden, Louie Gohmert, Michael Burgess, all of Texas; Paul Gosar of Arizona; Matt Gaetz of Florida and Mo Brooks of Alabama.

The senators want all guest worker visas suspended for 60 days, and after that, all new nonimmigrant guest workers suspended for one year or until national unemployment figures return to normal levels, whichever comes first. Along with H-1B visas, the lawmakers argue the suspension should include H-2B visas and the Optional Practical Training (OPT), which allows students to get anywhere from one to three years of job experience on a student visa.

Whether the White House has the legal authority to suspend guest worker visa programs remains to be seen. Court challenges by industry are all but certain.