Mercedes says its formal tie-up with Ducati is still in place and will remain valid unless the Italian bike company is sold.

Yesterday Audi was linked with a buyout of Ducati, even though the motorcycle firm has an existing marketing cooperation agreement with Merc offshoot AMG. That deal, established in 2010, was seen by many as a precursor to Mercedes purchasing Ducati.

But with Audi emerging as the favourite to to buy the firm – and take on its considerable debts – from parent company Ducati Motor Holding, a Mercedes spokesman said: "We have an agreement [with Ducati] and until such time that any purchase of Ducati is confirmed, either by Audi or anyone else, we will continue this agreement along the lines we have set out."

Volkswagen Group chiefs have remained similarly tight-lipped about the prospect of Audi buying the motorcycle brand. VW's chief executive Martin Winterkorn would not confirm or deny the rumour during yesterday morning’s VW Group profits press conference in Germany.

Ducati sells around 35,000 motorcycles per year. VW top brass have long been keen to add a motorcycle brand to their group’s portfolio, which includes Volkswagen cars, Audi, Seat, Skoda, Bentley, Bugatti, Lamborghini, Porsche, Volkswagen commercial vehicles and truck companies Scania and MAN.

A number of car makers, including Mini, Smart, Renault and Nissan, have moved towards offering two-wheelers or scooter-derived vehicles. BMW's Motorrad division has built motorcycles since the 1920s.

The trend is seen as a way of capturing both younger people who are unlikely to buy a new car until they are in their early 40s and offering branded and premium two-wheel mobility in the booming ‘megacities’ of developing nations.

The NSU name – once a major motorcycle brand – is also part of Audi, and there is said to be an outside chance that Audi may revive the badge for a new range of urban commuting vehicles.

Aside from the financial implications, a takeover by a major corporation such as VW would make sense for Ducati due to the huge advantages in terms of investment and access to new technology.