The ACI said its president Angelo Sticchi Damiani had been given a mandate to continue talks with Formula One on technical and commercial matters with the aim of signing a deal as soon as possible.
Monza was one of five circuits up for renewal after this season, the others being Spain, Britain, Germany and Mexico.
Britain's Silverstone, which hosted the first world championship Grand Prix in 1950, denied on Friday that a deal was done to secure that race's future.
"Unfortunately there is unsubstantiated news circulating this morning regarding the agreement of a new deal for the British Grand Prix at Silverstone," the circuit management said on Twitter.
"At this time we can confirm that we have not agreed a contract, however talks are still progressing."
Britain and Italy are the only two countries that have hosted a race in every year of the championship.
Vietnam is due to make its debut next season with a race in Hanoi while Zandvoort in the Netherlands looks likely to return for the first time since 1985.
The Motorsport.com website reported that Zandvoort could replace Barcelona on next year's calendar as the first race of the European season.
(Reporting by Alan Baldwin; Editing by Andrew Cawthorne)
