Mark Webber says Red Bull must resolve its problems with the KERS system or risk the championship.

So far neither driver has had a fully working system since the season began.

Vettel has managed to win twice but said the lack of KERS cost him the race in Shanghai on Sunday, while Webber's car had to be rebuilt at least four times over the weekend.

Webber said McLaren's experience with Mercedes in 2009 when they were using the system had helped and Red Bull must work as hard and clever as possible. 

Formula One is now on a three-week break until the next race in Turkey. Red Bull boss Christian Horner said they would be making the reliability of KERS a priority during that time.