(GMM) Honda is not yet ready to commit to Red Bull or Formula 1 beyond 2021.
The Japanese marque's F1 boss Masashi Yamamoto told the Japanese media source As-Web: "We are still negotiating with (Helmut) Marko."
But he also admitted that the talks are deeper than simply with Red Bull.
Asked if Honda wants to stay in F1, Yamamoto answered: "It depends on the conditions.
"After all, F1 is the pinnacle of motorsport, where the automotive industry can challenge and refine its technology."
He said it is possible Formula 1 will begin to lose that status as the new era begins from 2021, and there is also the threat posed by the future clampdowns on the sale of petrol and hybrid engines.
"It is also important how the fans see what they are watching," Yamamoto said.
"If they do not support anymore the fact that F1 is the best of motorsports, it will be less worthwhile for us to participate," said the Japanese.