United Airlines said Thursday it will dismiss fewer workers than previously announced after hundreds of additional employees were vaccinated for Covid-19.

The big US carrier said the number of workers scheduled to be terminated dropped to 320 from 593, after the airline announced Tuesday it planned to fire anyone who had not received the shot.

The airline revised its numbers following a surge in late vaccination uploads into its computer network. Airline officials expect to discover additional employee vaccinations once they initiate meetings with staff in line for termination.

"Our vaccine policy continues to prove requirements work," a United spokeswoman said in an email. "In less than 48 hours, the number of unvaccinated employees who began the process of being separated from the company has been cut almost in half."

United has been among the most aggressive large company in requiring Covid-19 vaccinations. In early August, the airline, which employs 67,000 workers in the United States, announced that all domestic employees would be required to receive the vaccine and upload their vaccine card into the company's system.

Chief Executive Scott Kirby urged other companies "to just do it" in terms of requiring vaccinations.

"This is the policy at United Airlines and you just have to make a choice as an employee," Kirby said in an interview with CNBC on Wednesday, adding that he believes the vast majority of employees will comply.

Coronavirus