Organisers of the Italian GP have admitted the new deal with Liberty Media saves them "a lot of money".
Liberty Media and Monza announced recently that after a period of uncertainty, they have now agreed a 2020-2024 race deal "in principle".
But Italian automobile club president Angelo Sticchi Damiani admits the actual contract isn't signed yet.
"It will take us about a month to discuss the contract with all the additions and important points," he told Rai radio. "I hope that it will be signed by July."
He admits the negotiations were fraught.
"It was very difficult to reach an agreement," said Damiani. "At first we had a very unfavourable contract, signed with Bernie Ecclestone in 2016.
"They kept saying 'Monza is important but also money is important. We have a waiting list from all over the world'. Two or three times it was close to breaking down.
"In the end we managed to reduce the financial requirements, but the negotiations were difficult. It is confidential, but compared to the initial requirements of Liberty Media, we saved a lot of money.
"They requested more than 24 million, but we managed to reduce the payments in the next five years. They are now very good conditions.
"I have to thank Liberty Media, because they realised the importance of Monza," he said.
