Red Bull Racing have once again brought up the threat of leaving Formula 1 over a delay in regards to the 2021 rules.
The teams have not yet reached a consensus over a new Concorde Agreement and F1’s parent company, Liberty Media, has made it clear that a level playing field in financial terms will be implemented going forward.
Red Bull have expressed their concern over budget cap restrictions, as they are the only top team not linked to a car manufacturer and engine supply (such as Mercedes and Ferrari).
Team principal Christian Horner admits that Red Bull boss Dietrich Mateschitz could pull the plug if he's not happy with the shape of F1 in 2021.
Horner told Autosport: "Absolutely. And that's his right. He's passionate about motorsport, he's passionate about F1, he's enthusiastic about the new engine partnership with Honda and the potential that brings.
"But of course F1 has to deliver for the Red Bull brand as well. It needs to be exciting, it needs to be cost effective, the racing's got to be great, and we need to be able to play on an equal and level playing field with OEM and manufacturer teams. I think like all of us he's waiting to see what F1 is post-2020."
Horner said a strong start to the Honda partnership is not essential to maintaining Mateschitz's motivation.
"Through good days and bad days he's always been tremendously supportive, and invested probably more into F1 than any other entity," said Horner.
"Two F1 teams, a grand prix [in Austria], plus all the promotion that Red Bull does around the world supporting F1, it's enormous. He wouldn't do that if he didn't believe in the sport."