Ever since we put the idea out there, the concept of Red Bull running Honda engines has gained momentum, and that was before it became clear that Renault intends dumping the Austrian team at the end of 2018.

Fact is however, with Mercedes and Ferrari ruled out, what other option does the Milton-Keynes based outfit have?

Team boss Christian Horner remains as evasive as however, refusing to shed light on his teams plans for 2019 and 2020.

"Everything is open for 2019," he tells the official F1 website. "Nothing is fixed. We will make a decision around spring to early summer next year.

Asked if Toro Rosso will be used as a testing mechanism next season, and whether he fears Renault might give priority to its new customer, McLaren, the Briton merely sought to further muddy the waters.

"Well, Renault has always provided a fair service," he says. "Every world championship, every Grand Prix victory we have achieved has been with a Renault engine... as a customer. They have always been very fair in providing equal services, so we have faith that this will continue.

"It's great that Honda remains in the sport and for sure, it is a great deal for Toro Rosso being a works team," he adds. "And, of course, from a Red Bull Group perspective it gives the opportunity to follow the progress of Honda before having to make a decision in springtime next year what our engine is for the future.

"McLaren will go through a natural honeymoon with Renault," he adds with a slight twist of the knife. "Fernando Alonso was their driver and so on, but we need to focus on our own business. As long as we get a fair service from Renault, that’s all we ask. And, of course, they want to bring up their own team, so we rely on their integrity as in all the previous seasons, in good and bad times, they have always provided parity of equipment."

And what of Aston Martin?

"Aston Martin is an interesting prospect," he admits, "and it will really depend on what the regulations are for 2021, on which we will get the philosophy of the FIA and FOM the week after Brazil.

"If it allows an independent engine manufacturer to be competitive, a company like Aston Martin could quite easily work with a third party like Cosworth.

"From our perspective it all will depend on what the rules are and if an independent could be competitive. I think it is important for Formula One - for the commercial rights holder - to have a competitive, independent, cost-effective engine."

And if the engine regulations don't witness a significant change, Horner is asked if his team will make further quit threats.

"Red Bull Racing has been around now for 13 years," he replies. "And prior to that we have been involved with the Sauber team and prior to that even as a sponsor, so we can show over 20 years of involvement. The desire is absolutely to continue. Red Bull is as committed as every team in the paddock.

"Of course we have our moments where the love of Formula One is tested," he admits. "And we have Max just signed to the end of 2020, so that is a pretty clear indication that we are not going anywhere!"