The suspect, who is being held by police in the Mediterranean city, has been named as 47-year-old Philipp Dutton by his lawyer, Nice-Matin newspaper reported.
Dutton was charged last month ago along with six other people, including a restaurateur, a paparazzi photographer, and a private detective, in connection with the kidnapping of Jacqueline Veyrac, the owner of the five-star Grand Hotel in Cannes and the seafront La Réserve restaurant in Nice.
She was found safe and well two days after her October 24 abduction in the back of a van the suburbs of the city.
Dutton’s lawyer, Benjamin Charlier, told Nice-Matin his client, who is from Liverpool, had confessed to police that he helped organise the kidnap but that he did not actually take part in it.
Dutton told his lawyer that he had served in the “special forces” in the British army and that he had been wounded, suffering severe burns, by a mine in Afghanistan in 2011.
The lawyer told the newspaper he had been unable to verify the suspect’s claims but that they seemed plausible to him and that he had what appear to be wounds from burning on his body.
Mr Dutton said he had three years of treatment for his wounds in various military hospitals and that when he returned to the UK he did not get a military pension. He said his personal life suffered after his injuries and that his Bulgarian wife had returned to Bulgaria with their daughter.
He said he then ended up homeless in Nice, often sleeping on the beach there, and it was there that he had meet one of the other suspect gang members.
An Italian named in local media as Giuseppe S. is the main suspect in the case. He leased La Réserve restaurant from the Veyrac family from 2007 to 2009 but he then went bankrupt.
He reportedly bore a grudge against the Veyracs, blaming them for his downfall.
Ms Veyrac had already survived a kidnapping three years ago, the motive of which was never discovered.
Police are investigating whether the suspects now in custody might have been involved in the earlier abduction attempt.