Team Lotus boss Tony Fernandes has stepped up his bitter fight with rival Group Lotus as both compete for the affection of home fans at this weekend's F1 Malaysian Grand Prix. The two groups are currently contesting a court case in London over the rights to the Lotus name in F1.

Fernandes, a Malaysian who is chief of budget carrier Air Asia, claims he bought the naming rights to the iconic F1 brand ahead of the 2010 season.

However Group Lotus, which makes Lotus road cars and whose parent company is the Malaysian government-owned car company Proton, has entered the sport this year as the chief sponsor of the Renault team and claims it holds the legal rights to the name.

Heading into this weekend's race, Fernandes made pointed remarks about Group Lotus, and the Mercedes team which is sponsored by the Malaysian government oil company Petronas.

"There will be three teams here with links to Malaysia, but only one team that has Malaysian blood running deep in its veins, with Malaysian staff contributing to our growth at every level and which has been built from the ground up in the same style as F1's grandee teams," Fernandes said. "We are enormously proud of what we have already achieved in just 18 months and we have done it through hard work and dedication, not by buying seemingly instant success through stickers on a car."

Proton managing director Syed Zainal Abidin Syed Mohamed Tahir was measured in his response yesterday, saying the Renault sponsorship was part of a considered marketing strategy as Lotus aims to strengthen its hand in the luxury car market.

"Lotus is an iconic brand as it is," he said. "But to support the development of the five cars in the future, we have to start the journey of branding. So it is a business decision and we believe that the branding and marketing opportunity in F1 for Lotus in particular is very high and that is again an example set by Ferrari, Mercedes, and so on.

"We have never said that we are a Malaysian company going to Formula One. It is a Lotus association and obviously as the shareholder of Proton, we are a national car company, there is some Malaysian involvement."