The Italian Automobile Club (ACI) says it has signed a deal with Formula One boss Bernie Ecclestone to keep the Italian Grand Prix in Monza for the next three years.

Ecclestone and ACI president Angelo Sticchi Damiani had already agreed verbally in September to terms.

Sticchi Damiani said “with a lot of work, despite a ton of difficulty, we’ve formally signed the contract for Monza”.

While details have not been announced, the deal is reportedly worth $US72 million ($A96 million), slightly less than the $US26.5 million ($A35.5 million) per year Ecclestone had requested.

No circuit has hosted more F1 racing than Monza. The venue was on the inaugural 1950 calendar and dropped off only in 1980 when Imola hosted the Italian GP.

Next year’s Italian GP is scheduled for September 3.