London - Formula One has a perfect opportunity to experiment with back-to-back races in Austria in July but Mercedes is standing in the way, Red Bull boss Christian Horner said on Monday.
The governing FIA and sport's commercial rights holders Liberty Media have suggested a reverse-grid qualifying race on the second Saturday to decide that Sunday's starting order and add to the excitement.
The idea would see qualifying replaced by a 30-minute race, with drivers starting in reverse order of their previous finishing position.
Mercedes opposed the idea when it was raised last year and were not supportive when it came up again at a meeting last Friday.
"I think we've got a unique situation this year, and having two races at the same venue - it would seem the perfect time to try something different at that second event," Horner told Sky Sports television.
"Otherwise, with stable weather conditions, we're likely to have the same output in race two as we have in race one.
"The only person that wasn't particularly supportive of it (the proposal) was (Mercedes boss) Toto (Wolff) because he thought it would interfere with Lewis' (Hamilton's) seventh world championship campaign, and it would be too much of a variable."
Sky quoted Mercedes as saying that "we don't believe F1 needs gimmicks to make it attractive. We believe in the sport to deliver excitement."
Mercedes have won both the drivers' and constructors' titles for the past six years and another for Hamilton would equal Michael Schumacher's record of seven.
Formula One has yet to start its season due to the Covid-19 pandemic but is expected to issue a revised calendar on Tuesday with a string of European races in quick succession.
Any change to the race weekend format has to be approved by all the teams. An online vote on the proposal is likely later this week.
Red Bull has won for the past two years at its home circuit in Spielberg with Dutch driver Max Verstappen.