Leading Formula 1 team principals remain unconvinced that V10 engines will power the sport again by 2028.
Talks are underway behind closed doors about potentially postponing the ambitious 2026 engine regulations, which introduce more electrified turbo 'power units'.
The alternative would see the FIA implement rules for simpler, lighter, cost-effective V10 engines running on 100 per cent sustainable fuel, reviving the classic high-revving sound by 2028.
"The romantic in you is hugely attracted to the idea of a screaming V10, so long as it's done responsibly and with fully-sustainable fuels," Red Bull's Christian Horner said.
However, some caution that such a drastic shift risks legal action from Audi and Honda, who committed to the 2026 grid expecting progressive engine technology, not a step back.
Horner acknowledged: "It's sort of ten past midnight and Cinderella's left the building. It would be a massive departure obviously to move away from what is currently being worked on very hard for 2026."
On this issue, Horner aligns with McLaren CEO Zak Brown.
"I don't really see how you can unwind what's in place, because of all the different power unit changes that are happening right now," Brown said.
"Audi's coming in, Alpine's going to Mercedes for an engine. Logistically, I'm not sure how you put the genie back in the bottle."
Alpine boss Oliver Oakes shared their reservations: "I think it's quite a romantic idea, but obviously the train has left the station now for 2026.
"I think it's probably something beyond that that will be looked at because it does sound quite good for Formula 1 to go that way a little bit," he said.
