The French judo star and five-times Olympic gold medallist Teddy Riner has announced plans to run in next year’s presidential election, describing himself as someone neither leftwing nor rightwing but who would seek to “bring people together”.

With more than five months before the April-May ballot to replace Emmanuel Macron, the race has been shaping up to be a showdown between political extremes. Polls point to a hollowing out of the political centre, suggesting that the anti-immigrant National Rally leader Marine Le Pen could be the frontrunner, with the radical-left leader Jean-Luc Mélenchon trailing behind.

Riner joins a crowded field of candidates, with analysts describing him as a long shot, given his lack of experience and no party backing.

On Monday, he sought to position himself as someone who would unite people and bring “common sense, steadfastness, justice” to France .

“I know what people are going to say about me: ‘He’s crazy. He’s not from the establishment. He doesn’t have the codes.…