(NEXSTAR) – American Airlines has no plans to resume full alcohol service until mid-September, a spokesperson for the carrier has confirmed.

In a memo issued to flight attendants on Saturday, an American Airlines executive announced the extended suspension of alcoholic beverage service for most of its passengers, aside from those in first or business classes. The memo also claimed that anxiety, confusion and fear among airline passengers may have contributed to “deeply disturbing situations” that unfolded on passenger aircraft over the past week.

“We also recognize that alcohol can contribute to atypical behavior from customers onboard and we owe it to our crew not to potentially exacerbate what can already be a new and stressful situation for our customers,” wrote Brady Byrnes, the managing director of Flight Service Training and Administration for American Airlines, in the memo.

American Airlines initially suspended alcohol service in its main cabin in March 2020. A spokesperson for the airline confirmed the suspension would remain in effect through Sept. 13.

Sept. 13 is also the date that the federal mask mandate is set to expire for all transportation networks — including on planes and in airports. The airline did not reveal whether its current alcohol policy would be amended should the federal government announce an extension to its mask mandate.

Byrnes did not elaborate on the “deeply disturbing situations” he referred to in the memo. The Federal Aviation Administration (FAA), however, has previously noted a “disturbing increase” in violent or disruptive behavior as far back as January, when the agency announced its zero-tolerance policy for unruly passengers. The FAA specifically noted a “proliferation” of such conduct stemming from passengers’ refusal to wear masks, and “following the January 6, 2021 violence at the U.S. Capitol,” according to an order signed by FAA Chief Steve Dickson.

Earlier this week, Lyn Montgomery, the president of the Southwest Airlines flight attendants union, also described some of the disruptive behavior in a letter to Southwest CEO Gary C. Kelly,  including one incident that resulted in a flight attendant suffering facial injuries and the loss of two teeth.

In her letter, Montgomery specifically outlined the union’s concerns regarding resumed alcohol service, especially amid an “already volatile environment.” Southwest Airlines is currently not offering alcoholic beverage services on its flights.

In addition to confirming that American Airlines would not be resuming alcohol service until September, Saturday’s memo reiterated the carrier’s zero-tolerance policy for the “mistreatment of our crews.”

“We hope this decision will underscore our commitment to that end,” Byrnes concluded in the memo.