American Airlines Group Inc. warned 13,000 employees that they could be laid off, many for the second time in six months, unless travel rebounds strongly or Congress provides a third round of federal aid by April.

The carrier will send out government-required WARN notices Feb. 5, Chief Executive Officer Doug Parker and President Robert Isom told workers in an email Wednesday. The warning came less than a week after United Airlines Holdings Inc. told 14,000 employees that their jobs may again be in danger.

The risk of new layoffs highlights how little travel demand has recovered amid heavy coronavirus case totals worldwide and tougher government travel restrictions. With vaccination campaigns still in the early stages, domestic airline passengers are at less than 40 per cent of 2019 levels. Foreign travel is at only about 15 per cent, the International Air Transport Association said Wednesday.

At the end of 2020 “we fully believed that we would be looking at a summer schedule where we’d fly all of our airplanes and need the full strength of our team,” the executives said. “Regrettably, that is no longer the case. The vaccine is not being distributed as quickly as any of us believed, and new restrictions on international travel that require customers to have a negative COVID-19 test have dampened demand.”

U.S. airlines furloughed workers in October when an initial round of US$25 billion in government aid expired. Then they recalled most of the affected employees after Congress passed an extension of payroll support in late December. That second round of funding, for US$15 billion, expires March 31. Airlines and labor unions are lobbying for additional federal assistance.

In hopes of reducing the number of job cuts, the Fort Worth, Texas-based airline also is offering a third round of voluntary separations and long-term leave options that frontline employees can choose, excluding pilots. American furloughed 19,000 workers on Oct. 1, on top of 12,500 who had left the company voluntarily and 11,000 who previously took leaves of varying duration.

Delta Air Lines Inc. has avoided furloughs, relying instead on 18,000 voluntary departures and 50,000 workers taking unpaid leaves of as long as a year. Southwest Airlines Co. also has said it won’t lay off any workers at least through 2021.