Red Bull, Toro Rosso F1 team bosses against Alonso's tyre war hope

On Wednesday double world champion Alonso argued F1 was better off when Michelin and Bridgestone went head to head from 2001-06.

Toro Rosso team principal Tost feels Alonso's judgment is clouded by the fact he won his two world titles in 2005 and '06 with Renault when Michelin firmly supported its fellow French manufacturer.

"I just hope there is no tyre war, no other tyre manufacturer," said Tost.

"This means two teams will have the good tyres and the rest will just get the scraps, like it was before.

"When Michelin was in, it was Renault [favoured], therefore Alonso has good memories, and with Bridgestone it was Ferrari, which was one of the reasons why Michael [Schumacher] was so successful.

"If this comes back it would be the same story - two tyre manufacturers two teams, three tyre manufacturers three teams, and the rest get what the others don't like.

"That means we would have the power-unit Formula 1 and the tyre Formula 1, and while the power units are stabilised we then open up the next problem."

Red Bull team principal Horner was in full agreement, suggesting it would have been highly unlikely his team would have won four consecutive constructors' and drivers' championships if there had been a choice of tyre manufacturer.

"One make of tyre means equality for all of the teams," said Horner.

"In the times of tyre wars effort has go to behind your leading charge, which would drive up costs immeasurably as you'd have to develop your car around a specific tyre.

"It's been one of the successes in having a sole tyre supplier, and that's one of the reasons why Red Bull has achieved the success it has as an independent team.

"That is something we perhaps would not have enjoyed if there had been open competition, with tyre manufacturers aligned to automotive manufacturers, which is where their core income comes from."

The FIA has now officially opened up the tyre tender process for 2017-19 with Pirelli's current contract due to expire at the end of 2016.

While the FIA documents specifically call for a sole supplier, Pirelli motorsport director Paul Hembery recognises there is always scope to change.

"We're involved in 250 championships, of which about 90 are open competition," said Hembery.

"It depends what the sport wants, and then you have to understand the rules and what the cost implications could be, so you can't really offer an answer until you know the parameters.

"But the tender is for a single supplier, so in 2017 I might be here, or I might be on a boat drinking some champagne - probably better to be sat on the boat!"