Bernie Ecclestone wanted Monza's new deal to be for a full seven years, according to race consultant Ivan Capelli.
The F1 supremo and Italian Grand Prix officials finally announced last weekend that Monza's future on the calendar is secure at least until 2019.
However, Ecclestone usually prefers long-term, seven-year contracts rather than the three-year deal announced with Monza.
"Monza wanted to remain flexible, because in Formula 1 no-one knows what could happen," said Capelli, a former F1 driver.
It was expected that the 2017-2019 contract would actually be signed last weekend, but the parties said that it could only be done in London for jurisdictional reasons.
However, Auto Motor und Sport reports that the deal might actually be held up further by legal action being taken by rival race bidder Imola, after the Italian automobile club vowed only to support Monza.
"It is understood the Aci president intends to proceed with the signature on a potentially flawed contract before the decision of the courts," Imola declared in a statement last week.
Monza has been the home of the Italian Grand Prix since 19050, aside from its single iteration at Imola in 1980.
