Briatore warned he must start winning races

Flamboyant Formula One team manager Flavio Briatore has been warned that his Renault cars must mount a credible challenge for this season's world championship.

Briatore has embarked on a personal crusade to promote F1 as a spectacle but Patrick Faure, president of the Renault team, has told him that results are more important.

Renault won one race last year and Faure said: "Flavio wants to put on a show but there is a whole company which has invested a lot of money in F1. We are here to win races."