Raikkonen said the new car was a big improvement

Kimi Raikkonen said the car, featuring a new chassis and aeroydnamics, was a big step forward when he tested it at Silverstone last week.

The car will not be taken to the next races in Canada and the USA, Whitmarsh told Autosport magazine's website.

"France is realistic assuming the benefits warrant the risks," he added.

Whitmarsh, the head of McLaren's F1 programme, said the team's poor performance so far this season made it sensible to bring in the new car as early as possible.

The MP4-19 with which McLaren started the season has been a major disappointment.

The handling is much better but we still have problems with the shortage of parts Kimi Raikkonen New car in pictures

The team, title contenders last year, are a distant sixth in the constructors' championship having scored just five points.

"Inevitably the speed with which you bring things through depends upon a risk/benefit analysis," Whitmarsh said.

"f you're nowhere in the championship, and you're not scoring enough points - or any points - then you can be slightly less risk-averse."

He added: "If it goes like a train, two seconds a lap quicker, and doesn't have any issues, then I'm sure there will be some haste with which we bring it through.

"If it's a small incremental improvement and you have some issues, then you defer it."

Raikkonen said he was pleased with the behaviour of the new car at Silverstone.

"The handling is much better, which is good not just for me but for the team," he said.

"We did lots of laps but we still have problems with the shortage of parts which causes a delay in repairs, but it's been good."