Montreal Mayor Denis Coderre says there is no rift between the city and Formula One management over improvements to Circuit Gilles Villeneuve.

Coderre said Sunday ahead of the Canadian Grand Prix that a handshake agreement has been reached between F1 boss Bernie Ecclestone and the head of the city's executive committee Pierre Desrochers on enlarging the paddock area and other upgrades at the track.

Ecclestone cast doubt on the future of the race this week when he warned the city would be breaching its contract if improvements are not completed as agreed by 2017. The city pledged $32 million for the improvements as part of a multimilion-dollar deal reached two years ago to keep the race in Montreal until 2024. Work has yet to begin.

Coderre said plans were delayed by disagreements over which installations would be permanent and other details.

"There will be another deadline, but there's a handshake and we will finalize everything by the end of July," said Coderre.

"There's no problem," he added. "We needed some clarification regarding the paddocks and all that because when you're talking about millions of dollars, it's taxpayers' money, and if someone said 'this is what I want' and the other says 'no' and it takes a few months, of course you won't be able to fulfil the deadline.

"So we agreed we had to clear the air and check it out. We agreed on what we need to do and we will do it."