Audi has no plans to sell Lamborghini, a spokesman for the carmaker said after European media reports about a €7.5 billion (NZ$12.7b) offer for the luxury car brand.

"This is not the subject of any discussion within the group," he said. "Lamborghini is not for sale."

The Swiss Quantum Group, together with the British investment company Centricus, are planning to submit a “Letter of Intent” according to Automobilwoche, the German affiliate of Automotive News Europe.

Quantum boss Rea Stark Rajcic founded the sports car brand Piech Automotive two years ago with Anton Piech, the son of the former VW patriarch Ferdinand Piech. But the offer has little interest at parent Volkswagen Group and its Audi luxury unit.

Last year VW Group CEO Herbert Diess talked about separating Lamborghini but the board of directors disagreed.