Haas F1 team principal Guenther Steiner says the team is unlikely to sign an American driver for its 2016 debut as there is "nobody out there at the moment" with enough experience.
Haas is expected to announce at least one of its two drivers before the end of September, with Ferrari reserve and test drivers Esteban Gutierrez and Jean-Eric Vergne believed to be the prime candidates for one seat. American GP2 driver Alexander Rossi has also been linked with a drive since Haas' entry to the grid was confirmed last year, but his F1 experience is limited to four practice sessions over three seasons for the now-defunct Caterham team.
Steiner appears to have ruled out Rossi's chances of a full-time drive.
"There is nobody out there at the moment," Steiner told the official F1 website about signing an American driver. "Yes, there are drivers in GP2 and Formula Three, but having a rookie in a new team... that is difficult for both sides. The potential of such a partnership failing is pretty high. So at the moment we'd rather not be looking at that avenue, because you are also not helping an inexperienced driver - he could be burned in one season. We are new, so we need a known quantity in the team."
Steiner says the team's shortlist has narrowed down to two drivers.
"I don't want to drop names at this time, but we're pretty confident that by the end of September we will announce at least one driver. We are negotiating with two of them, but nothing is done. We are very close to some drivers - and at the end of September we will come forward. It is good to get another box ticked!"
Lotus driver Romain Grosjean and McLaren junior Kevin Magnussen have also emerged as rumoured signings in the past few weeks.