At the end of his most disappointing season since 2001, his second season in F1, Jenson Button has sent out a stark warning to his Japanese employers, Improve or I'm off.

In a season in which the Japanese team's highlights were having the Beckhams as guests at Silverstone (though the couple talked only of McLaren driver Lewis Hamilton), and beating Marks & Spencer by securing a Green Award, Button had to wait until the French GP before scoring his first point. A further point in Italy and a fortuitous fifth in China took his season tally to six points, and fourteenth place in the Drivers' Championship.

With his team finishing eighth in the 2007 Constructors' Championship, the 2006 Hungarian GP winner told the Daily Mail that unless his team improves significantly next season he is leaving.

"The car was a complete dog," he admitted. "I'm just not interested in racing like this any more. I remember after Hungary this year wanting to hit something," he continued. "I'd won that same race 12 months previously and now I was there sitting in something which was undriveable.

"I have to start winning and if I don't then I have to be ruthless," he added. "There's an option in my contract which means we can all sit down and discuss the future at the end of the season. If things don't work out, that's exactly what I'll be doing."

Looking ahead to 2008, he added: "I'm not saying I expect to win the world title but I do expect a dramatic improvement."

Meanwhile, despite Max Mosley's calls for cost cuts, our spies tell us that Honda is seriously increase its staffing levels, with one insider telling us that the team could increase its workforce over the coming months by as much as 20 percent. With that sort of expenditure, its not only Button who will be demanding a significant improvement.