Mercedes thinks it is "premature" for Formula 1 to be considering the idea of V10 engines before the next generation turbo hybrids have even run.
The idea of F1 switching to V10s powered by fully sustainable fuel from 2028 or 2029 has accelerated in recent weeks, with the FIA setting up a working group to speak to relevant stakeholders and work out if such a move has support.
Of the manufacturers signed up from 2026, it is understood that Red Bull and Ferrari are in favour of the concept, with Audi suggesting that it is against it. Honda's position has not been publicly clarified yet.
Mercedes is open-minded on F1's future engine direction, and not wedded to sticking with the turbo hybrids that have been around since 2014.
However, its motorsport boss Toto Wolff is clear that talks should not go too far before everyone agrees on what the ultimate objectives are.
He is adamant that F1 first of all needs to agree on this aspect before it can then settle on the specifics of adopting a V10 ruleset. Other proposals that could be evaluated are V8s, the use of turbochargers, and a Kinetic Energy Recovery System (KERS).
Speaking to The Race, Wolff said: "We need to remind ourselves that the engines that are going into effect in 2026 are regulations that have been put forward by the FIA, in order to accommodate newcomers such as Audi.
"It's a bit premature, in my opinion, before we have even started with those engines, to bring up a possible future concept.
"In order to acknowledge the standing of F1 as the biggest global sport that attracts vast audiences and the best car companies in the world, we need to cheer for any such sustainable new concept for 2026. I think that's the standpoint.
"If we were to decide that we want to discuss the future regulations, then most important is to do that in a meeting room, behind closed doors, and then come up with a concept and say that's what we want to do - because the world has changed. Fair enough, you need to be agile."
Wolff said he thinks the starting point for discussions should not be about whether or not switching to V10s is right but more about what F1 wants from the next engine ruleset.
"What are the new circumstances that we need to consider in terms of the real world?" he said. "What is it that we think we can optimise with the future engine in respect to what's coming in 2026, because 2026 was always the compromise in order to accommodate the newcomers?
"There's certainly interesting aspects of the discussions and rumours that have been brought forward that we see as an interesting challenge. But only as long as they are evaluated, and discussed in order. So what are we trying to achieve? What are the targets?"
He added: "We need to put some analysis behind it, and then decide collectively, because fundamentally, we all have the same objective. We want to make the sport great, we want to continue to make the sport greater. We'd like to attract the fanbase that we have."
While the idea of a V10 has excited many long-term followers who watched F1 decades ago, Wolff said he thinks it is important grand prix racing understands if the newer fans are so eager.
He also suggested that, while the screaming noise of those old engines is looked back on with rose-tinted glasses, unleashing them in the modern world could trigger complications - in stopping F1 becoming a family affair because it becomes too loud, and it prompting noise-pollution concerns for street race venues.
This is why one of the ideas that has been bandied about is for the future engine to become a turbo V8, with a potent KERS to include some form of electric power boost element.
Wolff said: "We need to bear in mind the demographic, where today we have lots of young people around and F1 is a family event.
"We need to consider the implications of the V10 engines, that are the rumour at the moment, down the Las Vegas Strip or in Albert Park. At least, when I walk through Albert Park, what I see is lots of kids, and it's become a weekend programme.
"This is just one example of all the factors that need to be considered when making a decision, rather than it just being the idée du jour."
