Dr Helmut Marko says there is "no deadline" for Red Bull to commit to Formula 1 beyond 2020.

At present, there is great uncertainty up and down pitlane about 2021, after Liberty Media finally published the sweeping new regulations and started negotiations for the next Concorde Agreement.

Mercedes, Renault and Honda are all showing signs that their commitment to Formula 1 could be fading. Even Red Bull is not rushing to sign up for 2021.

"There is no deadline, so there is no pressure," Marko, the energy drink owned team's top Austrian official, told Kleine Zeitung newspaper.

He said team owner Dietrich Mateschitz's decision will be made independently of the other top teams.

"No, it doesn't matter," Marko answered when asked if what Ferrari and Mercedes decide will influence Red Bull's call.

Elsewhere, there is scepticism about Liberty Media's 2021 vision.

Robert Kubica said he thinks the budget cap could fail to equalise the competition.

"It's true that money helps but it's talent that makes the difference. I hope it will put teams closer together but I have my doubts about it," the Williams driver said.

"We see in Formula 2 and Formula 3 that the cars are the same but in the end the talent of the people is even more powerful."

Former F1 supremo Bernie Ecclestone even doubts that the new cars, designed to make it easier for chasing drivers to overtake, will succeed.

"The regs won't do what they are meant to do because the problem is the drivers sit there looking for strategy to get them from third or second to first," he told the Daily Mail.

"They don't need to race. The people on the pitwall are racing more than the drivers," said Ecclestone.