The UK’s CAR magazine reports the agreement gives Audi until mid April to finalise the deal.
The purchase would benefit the Volkswagen Group, which owns Audi, by increasing its expertise in high-revving, lightweight engines and expanding its portfolio to 12 brands including Bentley, Bugatti and Lamborghini.
Reuters reports the Ducati purchase could be announced as early as April 18, one day before Volkswagen's annual shareholders' meeting in Hamburg.
While the buy-up is a significant move for the German manufacturer it’s not a new idea. Italian newspaper Corriere della Sera reported in 2005 that Audi tried to buy Ducati from its previous owner Texas Pacific Group but lost out to Investindustrial.
And in 2008, Volkswagen Group chairman Ferdinand Piech said it was a mistake not to have bought Ducati when it was on the brink of bankruptcy.
Despite the Bologna-based company producing about 40,000 motorbikes a year, Ducati is reportedly about 200 million euros ($255 million) in debt which Audi will absorb as part of its estimated 50 million-100 million euro ($64 million-$127 million) purchase offer.
Interestingly, Audi’s German luxury brand rival BMW bought the Swedish motorcycle group Husqvarna in 2007.
Ducati was founded in 1926 and has won 17 manufacturer's World Championships over the past 60 years - the most recent being the 2011 World Superbike title.