Prost angered over de la Rosa's Jaguar move

De la Rosa was announced as Prost's third driver two weeks ago and tested the team's AP04 at Estoril last week. However, stories emerged on Monday that the Spaniard was switching his allegiance to Jaguar, and he was confirmed as a test driver for the Milton Keynes-based team the following day.

De la Rosa is believed to have ignored warnings from Prost, before he signed with Jaguar, that he was under contract to the French team. Prost claims it has exclusive rights to use de la Rosa as a test driver and by signing for Jaguar the 29-year-old is in breach of contract.

The Guyancourt-based team believes de la Rosa has acted unethically and is pursuing the matter legally as a matter of principle.

A team spokeswoman said: "We intend to exercise our rights against him [de la Rosa] as well as against his representatives and agents and, if necessary, against our competitor [Jaguar Racing]."

De la Rosa's to move to the French team was thought to have been aided by manager Julian Jakobi, who used to work with four-time world champion and team boss Alain Prost. The former Arrows driver's late switch to Jaguar will be even harder to swallow after reportedly choosing de la Rosa over other potential candidates.

Despite having actually driven for Prost last week, de la Rosa is thought to have pulled out before any official documents were signed

"I understand all the arguments that are going around about me breaking a contract," de la Rosa told Spanish newspaper ABC. "I didn't sign any documents, or at least any that were binding. I tested with them in Estoril and then we continued negotiating."