Renault team boss Eric Boullier has insisted that Robert Kubica will return to an F1 race seat this season if he has fully recovered from the injuries he sustained in a rallying accident in February, despite the team having signed Nick Heidfeld as his replacement.

Heidfeld agreed a deal to replace Kubica while his former BMW Sauber team-mate is out of action, with the Pole having undergone surgery in recent months as he attempts to make a return.

Kubica's manager had suggested that he could make a return to action in Brazil and Boullier insisted that if the Pole is fit to make a comeback, Heidfeld would step aside - with the German aware of that situation when he joined the team.

"The situation is very clear," he was quoted by the Polish publication Sport. "We have an agreement with Robert and Nick is well aware that if Robert is recovered and able to come back, he will come back. End of story.

"There is no other possibility. I should know as I am the man who signed the contract! Robert is improving very quickly. After the last surgery he had to relax for some time but now he is pushing really hard. I haven't seen him lately but I've spoken to him a bit.

"I am also in constant contact with his manager Daniele Morelli and Dr Ceccarelli, who says that the situation is better than expected."