The US government is suing a Chick-fil-A franchisee for allegedly denying an employee's request to take Saturdays off work for religious reasons.

The lawsuit claims that Hatch Trick Inc, the franchisee, violated federal law by denying an employee's request to refrain from work on Saturdays for religious reasons.

The employee was a member of the United Church of God, which observes the Sabbath on that day, the US Equal Employment Opportunity Commission (EEOC) said in a press release.

The federal agency is a workplace watchdog set up to fight workplace discrimination.

According to the EEOC, the employee requested not to be scheduled for Saturday work during her initial job interview in August 2023.

Hatch Trick honoured this request for a few months before eventually requiring her to work on Saturdays in February 2024, despite the employee's request for religious accommodation, the EOCC claims.

The employee was responsible for managing the delivery drivers at one of Hatch Trick's Chick-fil-A locations in Austin, Texas.

According to court documents filed by the EOCC, the woman was paid hourly and worked 45 to 50 hours per week, Monday through Friday, as well as some additional hours on Sundays.

When she appealed to management, Hatch Trick allegedly told the employee that she could not maintain her managerial role if she did not work on Saturdays. Instead, they told her that she had to accept a delivery driver position, which entailed lower pay, reduced benefits and hours, the EEOC said.

She proposed a number of accommodations that would have allowed her to keep her role, including having a driver handle dispatch on her day off and working only after sundown on Saturdays, according to the EEOC complaint.

The watchdog agency said the company fired the employee when she refused to accept the driver position.

"Religious discrimination in the workplace is unlawful, and employers must make reasonable accommodations for employees' sincerely held beliefs," EEOC San Antonio Field Office Director Norma Guzman said.

The Sabbath is the holy day of rest in the Christian faith, which most Christians observe on Sunday. Chick-fil-A allows its employees to observe the Sabbath by closing on Sunday, giving them time "to rest, enjoy time with their families and loved ones or worship if they choose", according to the company's website.

Chick-fil-A declined to comment to the BBC but told ABC News affiliate KVUE in a statement: "It's important to know that, as a franchise business, all employment decisions are solely the responsibility of each individual restaurant owner."

The BBC has contacted Hatch Trick Inc for comment.