United Airlines Will Fire Nearly 600 Unvaccinated Employees Who Defied Mandate

United Airlines said that while 99% of its U.S.-based employees received the COVID-19 vaccine, the 593 who did not meet the vaccine mandate will be fired

United Airlines plane. Photo: Robert Alexander/Getty

United Airlines is firing hundreds of workers who refused to get the COVID-19 vaccine.

The airline is terminating about 600 U.S.-based employees who did not comply with their vaccine mandate by the company's Sept. 27 deadline, The New York Times reported Tuesday, although 67,000 employees — or 99% — did get vaccinated.

"This was an incredibly difficult decision but keeping our team safe has always been our first priority," United Chief Executive Scott Kirby and President Brett Hart said in a memo sent to employees and obtained by PEOPLE.

United has already begun firing the 593 employees who did not meet the vaccine requirements, a company spokesperson told PEOPLE. However, the unvaccinated staffers can can keep their jobs with the carrier if they choose to get the shot before their employment is officially terminated.

"We will work with folks if during that process they decide to get vaccinated," the spokesperson said.

Vaccine. Getty

In the letter sent out this week, Kirby and Hart acknowledged that the decision to get vaccinated "was a reluctant one," for some employees, before adding, "But there's no doubt in our minds that some of you will have avoided a future hospital stay—or even death—because you got vaccinated."

Under United's vaccine mandate, employees may can make the case for religious or medical exemptions. About 2,000 employees have sought such exemptions, per The Wall Street Journal.

While the major airline previously planned to put workers exempt from the vaccine on unpaid leave starting Saturday, the airline has since pushed the decision to Oct. 15 because of a lawsuit filed by six employees.

The company previously announced plans to require its employees to get vaccinated in early August. At the time, United required its employees to show proof of vaccination within five weeks of a vaccine being fully approved by the FDA or by Oct. 25. Weeks later, the FDA granted full approval to the Pfizer vaccine.

A United spokesperson told Reuters that the airline also plans to require that new hires are vaccinated, and is planning to hire around 25,000 people in the next few years.

While United is firing its unvaccinated employees, Delta, another major carrier, has imposed $200 fee on unvaccinated workers using the company's health plan. Like United, Delta also announced plans requiring that new hires are vaccinated.