FIA president Jean Todt is pushing to add two more teams to the Formula 1 grid, but is facing challenges from current competitors.
F1 last raced with 12 teams in 2014, as Caterham dropped away from the field following the maiden year in the turbo hybrid era.
Haas' arrival in F1 in 2016 brought the grid up to 11 teams, before Manor collapsed prior to the 2017 season, reducing the field top 10 teams once more.
"It’s always a long debate,” he said. “At the moment we have 10 stable teams.
“As you know we are talking together with the commercial rights holder [Liberty Media], with the teams, about the renewal of the Concorde Agreement [beyond] 2020. And we are considering a lot of things.
“Of course for me I think it would be better to have 12 teams. If you speak about that to the actual team principals they are not very happy about that because of course it will change financial distribution, so it will be different for them. But it’s part of the discussion.”
Todt added that he has the support of Liberty Media, F1's current commercial rights holders.
“At the end of the day the most important is not so much the number of teams it’s the quality of the team and the quality of the show.
"So that’s something we do fully agree together with Formula 1, with Chase Carey, with his team and we are working very closely together.”
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