United Airlines Holdings Inc <UAL.O> told employees on Wednesday that it has cut its flight schedule by 90% in May and possibly June, and to prepare for a smaller airline and workforce starting as early as Oct. 1.

In a memo, Chief Executive Oscar Munoz and President Scott Kirby said travel demand “is essentially zero and shows no sign of improving in the near-term” and warned that “the challenging economic outlook means we have some tough decisions ahead.”

By Reuters