The project to build a new stadium for the French Open has been blocked because of political issues, but the French Tennis Federation said on Wednesday that it was confident it will go ahead as planned.

Gilbert Ysern, the general director of the French Tennis Federation, said that the Paris mayor's office "was unsure of the project's outcome," and that time was now running out to launch the construction work.

"We have been told that it's now a complicated matter," Ysern said.

"City hall is facing strong opposition. But we will keep working very seriously on the project and this is of course our favorite option. We are a strong federation, and we will succeed."

The project is reportedly facing opposition from green members of the city council and residents living near the stadium, but Paris city hall said it remained committed to the project.

"Paris city hall and its political majority wants the French Open to stay in Paris," city hall said in a statement.

"We are well aware of the necessity for the French tennis federation to modernise its facilities to stay competitive. We want to find a solution in this area."

The federation announced earlier this year a project to build a new centre court with a retractable roof that could be in use by 2013 or 2014.

The new 14,600-seat stadium would be located about 450 metres from the current centre court and surrounded by two other smaller, covered arenas at a cost of 120 million euros ($A195.77 million).

"We have already injected a lot of money, an architect has been appointed and has already started his works. We can't lose our time. We have to build," Ysern said, adding that the federation has the concession to use Roland Garros until 2015.

Last May, the FFT chose architect Marc Mimram, who is well known as the designer of the overpass that connects France and Germany across the Rhine River in Strasbourg.

Ysern added the FFT would pursue other options - including the possibility of moving the tournament away from its historical site - in case the new stadium project falls through.

"We are thinking about the impact of such a relocation," Ysern said.

"When you want something and you understand it's not sure that you are going to get it, you have to think about other options."

The FFT hasn't determined a site yet but it would be difficult to build a new arena in Paris itself, with the organisers probably being forced to consider a move toward the suburbs if the initial plan is dropped.

The federation said another option was to build a retractable roof over the current centre court.

If the extension's project finally gets approved, the new facilities would also host the Paris Masters, which is currently played at Palais Omnisports de Paris.