Formula One’s most famous ménage a trois, will soon have to begin making decisions.

“We are looking at a lot of options, including getting out of Formula 1 if it’s bad for Renault’s reputation,” said Renault Sport boss Cyril Abiteboul back in March.

Of course ‘Lord Red Bull’ has also threatened to quit the sport since his favourite big bull team isn’t getting the same eyeball air time it used to when winning everything in sight.

Meanwhile, behind the scenes, Toro Rosso have been progressing nicely with their long term business plan. The team once called Minardi, has its base in Faenza Italy, and is just over 100km from the home of Ferrari in Maranello.

Since the regulation changes for 2010 banned Toro Rosso from sharing designs and components with Red Bull Racing, the team has developed its own aerodynamics department, together will a full internal supply chain from procurement through to production.

Franz Tost is impressed with the efforts of the team’s technical director: “James Key has built a strong technical team around him and this will help us to come up with a competitive cars in the future,” Tost tells Crash.net.

Toro Rosso are about to move into a new state of the art premises and rumours continue to grow that they and Renault could ditch their bigger and more brash co-lover from Milton Keynes.

“The next step for Toro Rosso is to work very close together with a manufacturer, because we have our unit formula and this means that if you’re not directing work in the development acting more with the manufacturer, then it’s difficult to come up with the performance you need to become a frontrunner,” Tost observes.

“This should be the plan of Toro Rosso. This is the reason I said if I know who has the team, the shares of the team, for the team itself it can only be positive.”

Franz is loyal to the Red Bull family, who after all write him a fairly large cheque each year to fund the Italian based outfit’s Formula One adventures.

Yet the repeated attempts by Tost and Toro Rosso to woo Renault in their direction appear to be in conflict with their paymaster’s favourite F1 team from Northamptonshire.

“Renault came into the picture because they said maybe wanted to be more involved in F1,” explains Franz. “They want to see a white and yellow car for their identification, for their brand, therefore there was a discussion to buy shares in Toro Rosso”.

This is a revelation indeed. Previously it has been exclusively those form the Red Bull family talking up the Yellow and White branding of Renault cars, whilst the French manufacturer has remained silent on the issue. Now we know serious talks have taken place.

“I saw no problem, it’s only positive. It’s an ongoing discussion. I think at the moment Renault will work very hard on the power unit side. Then they will take into consideration the next step and then we will see.”

Even more shocking is the claim the Tost says the topic of this proposed new liaison has never been raised in Red Bull land. “It’s never been discussed,” he confirms. “It’s never been taken into consideration. We don’t know yet.”

One thing is for sure. If Red Bull or Mateschitz were not content with all this talk of an Italian French union – Mr. Tost would have been silenced by now.

Meanwhile in Renault-F1-land, Alain Prost their ambassador is being all ‘bullish’ about future progress. Gone is the talk of quitting F1 and despite all the problems with their power unit, Prost doesn’t believe any permanent damage has been done.

“It cannot be good but I don’t think it affects the Renault brand,” the Frenchman said. “You should not forget this happens sometimes in motor racing, you can dominate and then you can lose the domination. You need to accept that.

Christian Horner will not be happy that Renault are now focusing on 2016, but Prost re-confirms this to be the case. “There is going to be some development. Maybe not enough for this year but it’s going to be for the next.”

Renault tried the Red Bull approach of sending unproven engines to race weekends, the result is that Riccirdo and Kvyat may end up using 8 or 9 power units by the end of the year.

As if pre-emting a salvo from Milton Keynes, Prost reminds us, “and don’t forget the performance of the car is not only the engine but also the chassis.

“It is not only black and white, you can see with performance of Toro Rosso with the same engine.”

There it is again. More signs of a flourishing romance.

But where does this all leave Red Bull? There has to be some plan in place. If Toro Rosso wander hand in hand together over the horizon in 2017, Red Bull Racing will require a power train.

Doing some kind of deal where Audi provides an engine for 2017 looks remarkably hopeful, unless progress is made soon.

Red Bull are unlikely to be offered or want a Ferrari or Mercedes engine long term, because this relegates them from top dog customer status for sure. The same would be true of Honda.

It would be amusing were Red Bull forced to take a Renault engine for 2017, and becoming the junior partner to a deal done between Renault and the Italian Bulls.

If Audi are intent on coming over the Maginot Line and across the English Channel, RBR can wait – but surely not for much longer.

If not, this leaves Cosworth and their moth balled blueprint for an F1 engine. The British engine manufacturer could well be receiving highly relevant information via Milton Keynes at present, as they quietly progress with their F1 programme.

Cosworth once dominated F1 for 10 years with their DFV engine, though in recent times it has been far less fashionable to be associated with the midlands based engineering firm.

Whether Red Bull Racing can ditch the high end Pepe Jeans image and get down and dirty with a pair of dusty cowboy’s Wranglers remains to be seen.

At the end of the day – Hobson’s choice may be they have to make.