Not for the first time, Bernie Ecclestone exerted his authority over Formula One and the sport's leading drivers with a few forthright words when he intervened to defuse a simmering row over the quality of Pirelli's tyres.

He also gave a clear signal of possible intent and assured the Italian company not only has security and backing during a difficult period, but, another long-term deal with the sport in prospect.

After hearing of continuing complaints from four-time champion German Sebastian Vettel of Ferrari, whose expletive-riddled anger had been aired widely after last month's Belgian Grand Prix, the sport's commercial boss issued a rare official public statement.

This said: "Pirelli has been a first class partner of Formula 1 during the five seasons in which it has been the official supplier of tyres to the FIA Formula 1 world championship.
"We continue to have full confidence in the safety, quality and suitability of its tyres. Within the constraints of safety considerations, which are always paramount, Formula 1 encourages Pirelli to provide tyre compounds with performance because tyre degradation contributes to the challenge and entertainment of a Formula 1 race.

"When doing so, Pirelli provides strong guidance to competitors about any performance limitations of the tyres supplied.
"Competitors should heed Pirelli's expert advice when setting their race strategy and tactics, and if they do not, it is at their own risk.
"We are entirely satisfied Pirelli was not at fault for any tyre-related incidents during the Belgian Grand Prix."

Risky

Ecclestone's support for Pirelli not only ended the immediate argument about their tyres following the high-speed blowouts suffered by Vettel, during the Belgian race, and fellow-German Nico Rosberg of Mercedes, during Friday practice, but also put the safety emphasis back on their teams.

Ferrari had chosen to run the Belgian race using a risky one-stop strategy for Vettel.

Ecclestone's comments come at a time when there is much speculation about who will win the next three-year tyre contract for Formula One, from 2017, with Michelin reportedly also in the running.

Michelin has made it clear that it would prefer to supply tyres that would last a full race distance and not degrade rapidly, thus requiring pit stops.

Ecclestone's statement added: "Pirelli has offered to provide to each car a single set of tyres to last for an entire event. While we know they would be very capable of it, a race with no pit stops would be less exciting.
"Thank you, Pirelli, for helping us to deliver excitement to Formula 1 fans."

In the wake of the blowouts at Spa-Francorchamps, and widespread amazement at their proposal to increase advised minimum tyre pressures by five psi this weekend, Pirelli also reacted again.

Defending world champion Lewis Hamilton of Mercedes had warned that an increase of five could "be a disaster" and, within hours, Pirelli were re-evaluating their advice.

Instead of five psi, they were considering only two, according to paddock sources. A final statement from Pirelli was expected after second free practice on Friday evening.