Christian Horner has declared it "inconceivable" Red Bull and AlphaTauri will run with different power units following Honda's exit from Formula 1 at the end of 2021.
Red Bull team principal Horner has confirmed that all options are being considered after power unit supplier Honda dropped its bombshell at the start of this month it would be quitting F1 in just over a year's time.
With Mercedes ruling itself out of becoming supplier, it leaves Ferrari and Renault as the remaining possibilities of the current PU manufacturers.
Horner and AlphaTauri team principal Franz Tost have made it clear, though, that the two Red Bull-backed teams come as a package and they will not be powered by different suppliers.
"It's very much a two-for-one scenario," said Horner, who conceded to being "hugely disappointed" by Honda's decision.
"Due to the synergy project, due to the integration of the drivetrain, then it's inconceivable to think the two teams could operate on different power units.
"That introduces all kinds of complexities, particularly with IP from the different suppliers, so it will be way from ideal to have the teams on different power unit solutions."
Supporting Horner's comments, Tost said: "We don't want to use a different power unit as Red Bull because we want to continue the synergy process.
"I don't want us at AlphaTauri to start once more designing our own gearbox, the complete rear suspension and all of this kind of stuff.
"We have a very close co-operation with Red Bull Technology and we want to continue with them, and therefore we want the same power unit as Red Bull Racing because of the synergies we have built up over the past years.
"We don't want to go back to where both teams have a different power unit, and we can't use any more the synergies, which is so important for both teams."
Before you go...
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