Lewis Hamilton's desperation to catch Red Bull's Sebastian Vettel is causing accidents and the Briton needs to "calm down", says Ferrari's Felipe Massa.

McLaren driver Hamilton's season has been marked by incidents, including one which ended Massa's Monaco Grand Prix.

This prompted Formula 1 legends Niki Lauda and Sir Stirling Moss to criticise Hamilton's driving style.

"When you have some difficult races, when maybe you're trying too much, you have to calm down a bit," said Massa.

"It would be better for him too, because he was paying for it.

"He was penalised in a few races. And it wasn't just with me, he even hit his own team-mate!

"But Lewis is a clever guy and I'm sure he is already knows this."

2011 DRIVER STANDINGS S. Vettel (Ger) Red Bull 186 points J. Button (GB) McLaren 109 M. Webber (Aus) Red Bull 109 L. Hamilton (GB) McLaren 97 F. Alonso (Spa) Ferrari 87 F. Massa (Bra) Ferrari 42

Hamilton's coming together with McLaren team-mate Jenson Button at the Canadian Grand Prix has been the low-point of an eventful 2011 campaign for the 2008 world champion.

Having been punished for two accidents in Monaco, Hamilton went to Montreal a fortnight later and got involved in three separate incidents in the first eight laps, the last being a collision with Button.

It was this episode that provoked Lauda to describe Hamilton, who was forced to retire with a puncture, as "completely mad".

But Button, who would go on to win the race, defended Hamilton afterwards, saying his team-mate was "a racer, a fighter" and "one of the best drivers F1 has seen".

For his part, Hamilton has reacted angrily to the comments about his driving style and has restated his intention to keep pressing hard to overhaul the dominant Red Bulls.

Vettel, the defending champion, comes into Sunday's British Grand Prix at Silverstone with a 77-point lead, having won six of eight Grands Prix this year.

Massa, who is sixth in the standings, 144 points behind Vettel, acknowledges the German is now the "complete driver" having ironed out the mistakes that once saw him record too many non-finishes.

quote I am still aggressive and quick and will keep pushing for victories

"Vettel is a good driver and he's got a great car, which is a great position to be in," said Massa. "He's learned a lot and has certainly had a great championship so far. But the season is not over."

Massa, who finished a very close second to Hamilton in 2008, downplayed suggestions that new rules coming into force this weekend could bring the Red Bulls back to the pack.

When asked about the banning of the Red Bull-pioneered "off-throttle blown diffusers" (an exhaust system that generates downforce), the 30-year-old said it was impossible to say what impact the change would have as all the top teams used the system and would lose performance.

A popular figure in the sport, Massa gained considerable sympathy for his return from a career-threatening accident in 2009, when debris from another car hit his helmet at high speed. That kept him out of racing for six months but his comeback race in 2010 saw him finish second behind team-mate Fernando Alonso.

Subsequent results have not been so good but Massa is adamant he is no less a driver than he was prior to his injury.

"We didn't have a great season last year but I believe in my team, my engineers and myself - I am still aggressive and quick and will keep pushing for victories," he said.

He also shrugged off speculation about his future at Ferrari, saying he had a contract for next season and may even stay longer at the team he has loyally served for five years.