Shares in British Energy rose as much as 6 percent early on Friday after French business daily La Tribune reported on its Web site that EDF's board had given the go-ahead for a takeover bid for the UK firm.
However, the paper said the French electricity group was only one of more than 10 potential suitors that would include Germany's E.ON and RWE and British rivals Centrica and Scottish and Southern Energy.
It said the UK government had appointed UBS to handle the sale of its 35.2 percent stake in British Energy.
Neither British Energy nor EDF were immediately available for comment.
Shares in British Energy, a nuclear power company, were up 5 percent, while EDF was up 0.8 percent.