Lotus Renault GP managing director Eric Boullier has pointed to the 'stability' of the Enstone-based outfit's driver line-up as one of its key attributes heading into the F1 2011 World Championship campaign - as he professed that Robert Kubica is dedicated to the team 'for the long-term' and expressed his conviction that Vitaly Petrov will repay the considerable faith invested in him last year.

Despite alleged overtures from Ferrari - ostensibly with a view to replacing the underperforming Felipe Massa -Kubica last summer pledged his ongoing commitment to the cause at Renault, by signing a new contract that will keep him at the former double F1 World Champions until at least the end of 2012.

Speaking at the launch of the boldly-liveried new R31 in Valencia yesterday (Monday), Boullier hinted that the team's relationship with the Pole will last rather longer than that, and the Frenchman added that provided Petrov - fast but frustratingly erratic during his maiden campaign of top flight competition last year - fulfils his side of the bargain and raises his game to the level that is expected of him, then Lotus Renault GP will benefit from one of the most competitive driver pairings on the grid in F1 2011.

"Our line-up is still a mixture of talent, experience and youth," the 37-year-old acknowledged. "Robert is clearly one of our strongest assets, and we know we can rely on his speed, commitment and dedication for the long-term.

"As for Vitaly, he showed us at the end of last year that he understands what we expect of him in 2011 and he was ready to commit to this. With a year's experience behind him, he will be able to approach the new season with more confidence and is ready to help the team raise its game. We took the risk of investing in him last year, and I'm sure we will see the benefit of that this year.

"Stability is important in any industry and especially in the very fast-moving F1 environment, which is intensively competitive on every level. Having stability in our drivers is one of the key elements in bringing this team back to full competitiveness - it will allow us to capitalise on what we learned last year.

"The new management, the drivers, the engineers and mechanics have all been working together for a year now and have spent that time understanding each other. Now is the time when we can capitalise on that bond and team spirit, which will only make us stronger."