With attendance numbers trending lower, the Italian Grand Prix at Monza is no longer an easy sale for race fans, a situation that is now calling into question the very future of the event at the legendary circuit.

Ferrari and Sebastian Vettel's prominent role in this year's world championship battle has apparently failed to boost Italy's interest, putting under financial pressure a venue contracted by F1 to host the Italian GP until 2020.

Angelo Sticchi Damiani, the president of the Automobile Club d'Italia sees only way for Monza to sustain its presence on the F1 calendar beyond next year: a significant reduction by FOM of its franchise fee.

"We closed last year's race with a strong loss, and the 2018 budget will not be different either," he told La Gazzetta dello Sport.

"It is clear that such a situation is not sustainable in the long term. The ACI is ready to do its part, but not under any conditions.

"[Chase] Carey has always told me that an F1 without Monza is unthinkable, and in four years it will celebrate its centenary. We agree on that, but we must also deal in facts."

In the interim, the ACI president is hoping the Scuderia will battle Mercedes for all its worth for the remainder of the 2018 season.

"A year ago Vettel had gone on holiday as the world [championship] leader, now he is in the role of pursuer," said Sticchi Damiani.

"My wish is the exact opposite of what happened a year ago, when from Monza onwards Mercedes took off."

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