Greenpeace has called on the UK and other countries not to work with the nuclear industry after energy giant EDF was found guilty of spying on the environmental group.
EDF, which owns and runs eight nuclear power stations in the UK and is leading the drive towards a new generation of reactors in this country, was fined 1.5 million euro (£1.3 million) by a French court in the espionage case.
The trial revealed a dossier that had been compiled on Greenpeace UK, which the environmental group said dated back to the period when the French company was moving into the British nuclear market.
Greenpeace's executive director in France, Adelaide Colin, said the fine and damages awarded to Greenpeace sent "a strong message to the nuclear industry that no one is above the law".
She added: "Instead of working with the nuclear industry, countries should invest in clean, safe sources of renewable electricity."
Greenpeace UK's executive director John Sauven said the company should give a full account of the action it mounted against its critics. He said: "As one of the six companies with a monopoly over electricity supply in this country and a major sponsor of the Olympics, EDF has a duty to come clean."
The verdict was reached on the day that EDF price hikes come into force for customers.
The rises are the lowest price increases by the Big Six energy firms, but will see the cost of gas go up 15.4% and electricity rise by 4% for consumers.
Mr Sauven added: "EDF could demonstrate real regret for its illegal spying operation by using its increased profits to help those in fuel poverty, and by investing in renewable energy and energy efficiency."
EDF refused to comment on the court case.