President Trump is reportedly considering a guest worker proposal that has conservative immigration hawks ringing alarm bells.

In recent months, the administration has reportedly been in negotiations with senators about legislation that would “create new categories of temporary worker visas or lengthen the allotted stays for those workers,” among other things, according to Politico.

The effort comes after a larger, bolder White House immigration plan failed to gain support in congress.

The Trump administration has already massively expanded the H-2A temporary foreign agricultural worker program.

The White House confirmed to Politico that negotiations on the proposal are ongoing.

“We’ve also been listening to stakeholders,” a White House official said. “We’ve also developed points of view on what the temporary system should look like.”

A broadening of temporary worker visas is a policy change the business community has long sought, arguing companies in industries like construction and agriculture can’t hire enough workers to meet demand. But immigration activists seeking to reduce migration worry such changes would raise the number of foreigners coming to the U.S.

That such legislation would be considered during an election year after the president has repeatedly vowed to curb immigration, has some conservatives scratching their heads.

“I can’t wrap my head around why some Republican senators and administration officials are urging President Trump to embrace a guest worker expansion in an election year, or even worse — an agriculture amnesty bill drafted by an impeachment manager,” said RJ Hauman, government relations director at the Federation for American Immigration Reform, which wants to reduce the number of immigrants in the country.

According to Politico, the talks began after the House passed a bill focused on changes to the agricultural guest worker program. The legislation was introduced by House Impeachment manager Rep. Zoe Lofgren (D-Calif.).

The guest worker negotiations are separate from ongoing, more expansive talks about a 600-page draft bill that would grant permanent status to more high-skilled, well-educated immigrants while reducing the number for those who enter the U.S. based on family ties. Trump unveiled the contours of that proposal in May but has failed to garner support for the offer. Since then, Trump has decided a narrow deal to bolster various industries like agriculture — which has been coping with a shortage of workers and the fallout from Trump’s trade wars — could be worthwhile even if it risks alienating some in his base, said one of the sources, who has spoken to the White House about the issue.

One of the sticky issues in the deal is reportedly language addressing the 800,000 “Dreamers” who are fighting for permanent legal status. Dreamers are illegal immigrants who came to the United States as children.

Trump in 2017 attempted to halt the Obama-era Deferred Action for Childhood Arrivals program, but two federal courts ruled that it should continue until the Supreme Court weighs in. That decision is expected this summer.

As the unemployment rate has fallen, business groups have lobbied the Trump administration to create more slots for immigrants coming to the U.S. to fill available jobs.

An estimated 440,000 workers were needed in 2019 alone to meet the construction backlog. Because of this, the Associated Builders and Contractors has urged the White House and Congress to expand guest worker programs, “including creating a visa for less-skilled workers to do year-round nonfarm work,” according to Politico.

“It is critical a market-driven visa program for guest workers is established to meaningfully impact the U.S. workforce shortage and allow the construction industry to thrive,” said Kristen Swearingen, the group’s vice president of legislative and political affairs.

The number of immigrants with temporary visas has steadily increased during Trump’s presidency, reaching 925,000 in 2018, according to the Migration Policy Institute. While there is no cap for the total number of temporary workers, there are annual limits on some of the more than dozen visa categories. Changes to the program could include adding new categories of visas, adding new occupations and lengthening the allotted stays. The Trump administration has already raised the number of nonagricultural seasonal workers — such as crab pickers and life guards — the U.S. brings in each year. Last year, it increased the caps by 30,000 for a total of 96,000.

Agriculture Secretary Sonny Perdue, who has pushed for changes of the guest worker programs, has been involved in the talks, according to the four people. Perdue senior adviser Kristi Boswell was dispatched to the White House to work on immigration. The Department of Agriculture didn’t respond to request for comment.

The House bill eases restrictions on hiring agricultural workers and provides legal status and a path to citizenship to hundreds of thousands of immigrants who received temporary visas. That bill passed with 34 Republican votes.

The Trump administration’s previously unsuccessful bill had provisions that would have allowed “guest worker programs to address both seasonal and year-round jobs and create visas that would allow stays of 36 months.”

Sens. Lindsey Graham (R-S.C.) and Thom Tillis (R-N.C.) are reportedly leading efforts in the Senate to pass the bill.

Rep. Chip Roy (R-Texas) sent a letter to Graham this week urging him to stay clear of any language that focuses on “amnesty.”

“You know this issue — and the politics — better than most,” he wrote. “It would be a fool’s errand to pass such legislation which would directly conflict with the core campaign promises of President Trump to regain control of our border and immigration system.”