Former French prime minister Alain Juppé has conceded France's nuclear testing in the Pacific has impacted on the environment and peoples' health.
Mr Juppé was Prime Minister from 1995 to 1997 under President Jacques Chirac, who made the controversial decision to resume nuclear testing in French Polynesia.
That decision led to riots in Tahiti in 1995, and testing was eventually ended in 1996.
Mr Juppé, 70, is a member of the right-wing Les Républicains, and has been considering a bid for the French presidency in 2017.
The lobby trail this week led him to Tahiti where he met with several of the territory's anti-nuclear organisations.
After a two-hour meeting, Mr Juppé emerged to say the assertion France held until 2009 that its nuclear testing programme was clean was not based on fact.
"The affirmation which was to say that nuclear tests were clean is not right," Mr Juppé said.
"It is not the truth. Nuclear tests had, and still have, an impact on the environment which is worrying, it also has an impact on peoples' health."
Mr Juppé, mayor of Bordeaux in south-western France, said he would modify compensation laws to allow more people to claim for the effects of nuclear radiation if elected as president next year.
Despite receiving more than 1000 applications, the French state only ever granted 19 people compensation for harm caused by nuclear testing at Mururoa and Fangataufa atolls between 1966 and 1996.
Current socialist president François Hollande also promised to revisit compensation laws when he visited Tahiti in February.
But with Mr Hollande's popularity hovering between 10 and 15 percent in opinion polls, and with terrorist attacks and other events in mainland France drawing attention, the compensation issue was unlikely to be visited this term.
However, the legacy of decades of nuclear testing lingered in French Polynesia, where the effects of the 193 tests and the secrecy of the French state remained contentious.
It took until 2009 for Paris to acknowledge that harm had been done.
Frustrated with a lack of progress, the French Polynesian Assembly in 2014 passed a motion to ask France for close to $US1 billion in compensation, and Richard Tuheiava, an assembly member, last month pressed the case at the United Nations, something which Mr Juppé urged against.
"We will look for the path to reconciliation," he said. "We need to trust each other again."
Nuclear Workers' Association Mururoa e Tatou president Roland Oldham welcomed Mr Juppé's promise, with a dose of cynicism.
"I'm used to politicians," he said. "They speak one language one day, then when they are elected they are not capable of keeping their promise.
"So I will wait. If he becomes president then we'll seek to get him to change what he promised to."
"We told him that it was a very strong injustice that we have been facing for the past few decades," Mr Oldham said.
"It is also the attitude the French government has ... I think it is very important for the French government to change their attitude. That's what we told him today."