Jaguar team principal Tony Purnell has revealed that Mark Webber will have an 'upgraded' engine at his disposal this weekend.

Talking at the post-practice press conference, Purnell said: "This race we have got an upgrade that we are trying with Mark. We have just built one engine and we will see how it goes.

"It is always a risk when you try an engine for the first time," he admitted.

As previously reported, Webber, who has a contract with Jaguar for 2005, has a clause in his contract whereby if Jaguar is not in sixth position in the Constructors' Championship after this race, he is free to look elsewhere. In order to achieve this, basically the green team would need to win Sunday's race. Though this is virtually impossible, the team will hope that Webber will this as a sign of its intent.

Asked about rumours that Jaguar is not running its engine in the same configuration as Jordan, Purnell replied: "Eddie (Jordan) does get the same engine as us. The contract allows for a significant upgrade mid-season, which will happen.

"There are small variations between the engines," he added, "but on the whole, up to this race actually, there hasn't been a time when, we could have picked the engine number out of a hat and distributed it in that way.

"Although for this race we have got an upgrade that we are trying with Mark, we are trying to keep the engines on par as much as is practically possible."