Formula E puts €25million price on 12th entry slot

The electric single-seater series is set to expand from 10 teams, with Formula 1 champion Mercedes reserving one of two planned additional spots.

Formula E's founding teams had to commit to the series for a certain number of years and prove they had the funding to do so, as well as put an initial deposit on the cars, but they did not have to pay an entry fee.

Mercedes could join as early as the 2018/19 season, but Agag told Autosport he was not concerned about rapidly bringing in a 12th entry and the €25million entry fee was a reflection of that.

"I don't know if there's people who are ready to pay that money or not but what I want to do is protect the ones that are already here," he said.

"Everyone here, especially the privateer teams, has invested a lot of effort, a lot of human resources, a lot of money, to be in the championship.

"They deserve a value in return.

"Teams are starting to get into a financially good position but we need to be restrictive in the entries we give and give them to the right brands and at the premium because the ones already inside have invested that kind of money."

A Mercedes entry would join Jaguar, Renault, BMW and Audi as established motorsport manufacturers competing in FE, with emerging marques DS, NextEV, Mahindra and Faraday Future and electric-vehicle specialist Venturi also fielding teams.

Techeetah is the only remaining independent team in the series but the entry it succeeded, Team Aguri, was understood to be negotiating with Nissan, which has openly evaluated an FE entry.

Agag did not say whether Nissan was on the verge of joining the series but confirmed "good discussions with some" Japanese manufacturers were taking place.

"Having a Japanese manufacturer would be very important, but let's see," he added.

"We want to be as global as possible.

"It's going in the right direction and the momentum is right for more to come."