LONDON (AP) — Shares in British Energy Group PLC rose more than five percent on Friday after the nuclear generator disclosed that it had received takeover bids higher than Thursday's closing share price.

The revelation boosted speculation of a bidding war for British Energy, the largest producer of electricity in Britain with eight nuclear power stations and one coal-powered station.

The company, which is 36 percent owned by the government, said it had received a "range of proposals from several parties," including proposals priced higher than Thursday's closing price of 680 pence (US$13.23 euro8.55). That would value the company at around £10.9 billion ($21.2 billion). The stock closed up 5.2 percent at 715.5 pence ($14) on Friday. British Energy did not indicate whether the offers were cash or share, and added standard warnings under the takeover code that there was no certainty of a firm offer being made.

"A further announcement will be made in due course," it said, adding that discussions with the preliminary bidders were likely to continue for "a number of weeks."

Electricite de France SA, Britain's Centrica PLC, Germany's RWE AG and Spain's Iberdrola SA have all been named by analysts as potential suitors.

Evolution Securities analyst Lakis Athanasiou said a bidding contest is looking more likely.

"Speculation that only EdF had made a bid, with some reports putting the bid as low as 650 pence ($12.65), was misleading and contributed to price weakness in recent days," he said. "We continue to believe that the likeliest outcome is a non-contested bid with a value of 750 pence ($14.60)."