Toyota has been given a boost ahead of the Le Mans 24 Hour race with petrol-driven hybrid and non-hybrid LMP1 prototypes granted a fuel tank increase.
The Japanese carmaker, which is still searching for its first Le Mans victory, was left reeling after Audi swept the podium at the Spa round of the World Endurance Championship.
In response the FIA endurance committee has lifted the fuel capacity of the leading petrol prototypes by three litres.
The Toyota TS030 Hybrid will now carry a capacity of 76 litres. By comparison the Audi R18 e-tron Quattro cars have a capacity of 58 litres of diesel.
Privateer LMP1 petrol-powered Le Mans entries such as Rebellion and Strakka will be permitted to run an 83-litre fuel capacity which they can maintain after the 24 Hour classic.
 The concessions come following Audi seemingly able to turn its performance up or down at will.
Audi has dominated the opening rounds of the WEC this year while its turbo-diesel engined LMP1s have taken a stranglehold on the Le Mans 24 Hour, enjoying a dominating run since 2006.
Adjustments have also been made in the GTE Pro class ahead of the Le Mans 24 Hour from June 22-23.
The minimum weight for the Aston Martin Vantage has been lifted by 10kg and a larger restrictor has been granted for the Porsche 911 RSR.