Renault's existing drivers are still in the running for the race seats in 2017, according to Frederic Vasseur.
The French works team's boss was speaking after the 'silly season' heated up at Monza with announcements by Felipe Massa and Jenson Button.
"By late September, early October, it should be a lot clearer," Vasseur told France's RMC Sport.
"Part of my job is to keep an eye on all the drivers in the paddock and the other series. Of course this includes the team's drivers, because I know them well," he said, referring to Kevin Magnussen and Jolyon Palmer.
"Compared to the others, they have the advantage of being here and creating a link between themselves, the engineers and me.
"I also know that, for the future, drivers will be key. Not only for results, but also for the motivation of the team."
It is believed that Esteban Ocon, who has just been promoted from being the Renault reserve to the Manor race seat, is in pole position for a 2017 seat.
"Esteban is someone I know very well," said Vasseur. "He drove for me in the past and I saw him grow. I know his level of involvement and determination. He knows where he comes from and where he wants to go."
The championship continues in two weeks' time in Singapore.
