Team boss Gunther Steiner says he is waiting to hear if Haas owner Gene Haas will commit to Formula 1 beyond 2020.
The American team had a poor 2019 season - its fourth on the grid - and boss Steiner has already admitted that Gene Haas is contemplating the future.
"First of all, no one is sure that they will be here in 2021, because no contracts have been signed," Steiner said in Brazil, referring to the expiring Concorde Agreement.
"It does not depend on me what we will do in 2021, but anyway we cannot stop development. We must continue as though we will continue to be in F1."
As for Gene Haas' deliberations, he admitted: "There has been no progress for a couple of weeks, but I hope that there will be news next week.
"He must understand what he wants to do, so we wait patiently for that. It's a serious decision for him and I understand that he needs time to weigh everything up properly."