McLaren racing director Eric Boullier lost his calm at a press conference. File picture: Matthew Childs / Reuters.

Woking, England - McLaren's temperamental bosses lashed out at their critics during a heated press conference at the French Grand Prix.

Sportsmail revealed that staff at the team’s Woking factory are angry with their "clueless" leadership, who insult the workforce by rewarding them for hard work with 25p chocolate bars.

As Mercedes’ Lewis Hamilton tore to the fastest time in practice on Friday, there were frantic discussions between McLaren’s senior management.

But when racing director Eric Boullier faced the media, he lost his calm, accusing a journalist of lying for saying, correctly, that fellow executives are briefing against him. At the back of the room, McLaren PR chief Tim Bampton tried to get the questioning stopped.

Boullier, who gave a muddled performance, made the extraordinary admission that McLaren will never win the world championship with Renault.

"You can win races as a customer but winning a championship is another level - you need works team status," he said.

Boullier is in his fifth season at McLaren and has presided over a period of failure - they last won in 2012.

But he refused to resign, adding: "We are with a new Renault engine partner and we have a good team of people. We know where the issues of the car are."

But the heart of the problem is that he seems to have no idea what the car’s issues are or how to fix them. If he did, Fernando Alonso and Stoffel Vandoorne would not have spent yesterday two seconds off Hamilton.

The four-time world champion, with a new engine, was seven-tenths quicker than Daniel Ricciardo’s Red Bull.