Audi has revealed the updated R18 e-tron quattro LMP1 that will contest the 2016 FIA World Endurance Championship.

The German manufacturer confirmed that the new car will continue to use diesel power - setting it apart from its petrol-powered Toyota and Porsche competitors - as part of a revamped 4-litre V6 engine.

It also revealed that the car will be entered into the 6MJ energy retrieval sub-class, up from 4MJ on this year's model, which finished runner-up to Porsche in both teams' and drivers' competitions in the WEC.

Flywheel energy storage for the hybrid system has been abandoned in favour of a lithium-ion battery solution similar to that used by sister manufacturer Porsche.

The car also features heavily revised front bodywork in a bid to maximise aerodynamic performance.

"With our new Audi R18, we’re setting a clear signal: Audi continues to put the pedal to the metal in motorsport, deliberately relying on TDI – the world’s most successful automotive efficiency technology – at Le Mans," said Audi motorsport boss Dr Wolfgang Ullrich.

Audi also confirmed unchanged driver line-ups for the WEC, while also announcing it will scale back from three cars to just two for the Le Mans 24 Hours - along with Porsche.

Gallery: Audi unveils 2016 WEC challenger