President Biden’s nominee for the position of labor secretary has come under more fire from Republican senators after one of her underlings said a visa program used by American farmers was rampant with “traffickers” and “wage theft.”

In a Monday letter to acting secretary Julie Su, seen by The Post, Sen. Bill Cassidy (R-La.) raised comments by a senior Department of Labor official attacking the federal H-2A visa program, which temporarily lets farmers hire non-immigrant agricultural workers when US citizens are unavailable.

Mike Rios, who serves as regional enforcement coordinator at the department’s Wage and Hour Division, called recruiters hired to headhunt foreign workers “traffickers” and said the program amounted to “the purchase of humans to perform difficult work under terrible conditions, sometimes including subhuman living conditions,” according to an April 14 report from the left-wing outlet Prism.

“You can throw a rock and hit a violation in the agricultural industry,” Rios also said, telling the outlet that wage theft was “baked into” the federal program.

In a separate podcast interview, Rios also described the H-2A program as “literally buying people to come to do terrible work.”

Cassidy — the top Republican on the Senate Health, Education, Labor and Pensions Committee — and Sen. Tedd Budd (R-NC) told Su they found Rios’ remarks “troubling.”

“Mr. Rios’s claim that the H-2A program is equivalent to human slavery … finds no support in law or fact. It is also inflammatory and unbecoming of a senior federal official,” they wrote.

“This bias against the H-2A program appears to be part of a disturbing pattern during and before your tenure at DOL that demonstrates a disregard for the even-handed enforcement of our nation’s laws.”

Cassidy and Budd further stressed that if Rios’ comments were accurate, Su was either neglecting her duties or exhibiting a “startling bias against American farmers.”

“If the officials tasked with enforcing the H-2A program believe the system amounts to ‘wage theft’ and ‘the purchase of humans to perform difficult work under terrible conditions,’ then either DOL is currently unable to competently enforce the law or these statements reflect a startling bias against American farmers who use the program,” they wrote.

“As Acting Secretary, it is your responsibility to ensure that federal law is enforced fairly and without bias or prejudice.” 

Federal law requires farmers to pay H-2A workers “a wage that is at least the highest of” the Adverse Effect Wage Rate, meaning foreign laborers earn no less than US agricultural workers, Cassidy and Budd noted.

Additionally, they said, farmers who employ the hired hands must provide housing and cover the costs of transportation from a worker’s home country to the US.

The US has about 9.9 million job openings and just 5.8 million unemployed workers, according to the latest data from the Chamber of Commerce.

Rios’ remarks may complicate Su’s confirmation vote in the Senate, which a GOP aide told The Post could come as soon as this week.

Biden nominated Su in February to become the full-fledged head of the Labor Department, despite her overseeing billions of dollars worth of fraudulent COVID-19 unemployment handouts as California’s labor chief.

If confirmed, Su would replace former Labor Secretary Marty Walsh, who left the administration in March to head the National Hockey League Players Association.

Republicans on the committee have previouslyexpressed worries that Su did not perform her duties impartially while serving as Walsh’s deputy or as California’s labor secretary.

The senators have given Su until May 19 to clarify the Labor Department’s “role in enforcing the H-2A program” and ask whether she agreed with or knew about and planned a response to Rios’ comments before Prism’s report.