The number of people who can’t fly Delta just keeps rising.
“Wearing a mask is among the simplest and most effective actions we can take to reduce transmission, which is why Delta has long required them for our customers and our people,” Bastian wrote in the memo.
“As of this week, we’ve added 460 people to our no-fly list for refusing to comply with our mask requirement,” he added.
A spokesperson clarified to Fox News that the number represents the cumulative total number of customers on the list.
Delta first announced its mask policy for customers and employees in April.
Three months after announcing the new policy, the airline had put 120 people on its no-fly list for refusing to comply and wear a mask, according to a memo dated July 23, which was obtained by FOX Business in August.
However, by the end of August, Delta’s no-fly list doubled.
In an Aug. 27 memo, Bastian told employees that 240 customers would not be allowed to fly with the airline because they refused to cooperate with its mask policy.
Though all airlines have mask policies for customers, Delta has continued to block off its middle seats, while other airlines have made those seats available to people.
On social media, Delta recently poked fun at other airlines for opening middle seats up.
“A haunted house, but they’re not blocking middle seats,” the airline wrote on Twitter Thursday.
The gibe came following Southwest Airlines' recent announcement that it would once again start booking middle seats on flights as of Dec. 1, after previously capping passenger cabin capacity in May to enhance distance in the fight against COVID-19.
During Delta’s third-quarter earnings call last week, Bastian said the airline wouldn’t open those seats up until customers feel comfortable and are more confident in air travel -- which he expects will be the first half of 2021.
Fox News’ Janine Puhak contributed to this report.