It's understood that the FIA has performed a rapid U-turn over a new ruling aimed at ending the current practice of using the engine management systems to gain an aerodynamic advantage.

A number of teams, including championship leaders Red Bull, are currently gaining an advantage by using their engine management systems to continuously keep exhaust gasses flowing through their rear diffusers, thereby creating additional downforce, even when drivers are not on the throttle.

Speaking to reporters at Silverstone today, at the launch of the Northamptonshire circuit's new pit and paddock complex, Mercedes team principal Ross Brawn revealed that the FIA is aiming to crack down on the practice in time for this weekend's Spanish Grand Prix.

"The FIA clarified some rules on engine management systems which I think are going to affect all the teams," he said. "The sort of staccato exhausts that you currently hear, I don't think you will be hearing any more.

"The teams have all been developing their engine management systems to take the maximum advantage from the exhausts and the FIA want to push us in a different direction now so there will be changes there," he added.

With Red Bull having won three of the first four races and enjoying a 43 point lead over McLaren, the Englishman was asked if the new ruling would particularly hit the Austrian team. "I think it's forced all the teams to have a fresh look at what they are doing on engine strategies," he diplomatically replied.

However, it has since been revealed that the FIA has opted to postpone the introduction of the amendment to the regulations until after this weekend's race.