The group, which also owns a coal-fired power station at Eggborough, East Yorkshire, did not disclose the names of the companies involved, but said it planned to hold discussions with all the parties over the next few weeks.

British Energy said: "The board wishes to stress that each of the proposals requires further development and that the process is therefore likely to continue for a number of weeks."

It said the proposals included offers above the company's closing share price last night. European energy giant EDF is seen as the favourite to land the company, given its experience in running nuclear power stations in France.

However Spain's Iberdrola, which owns Scottish Power, and German industrial group RWE are also likely to be in the frame.

British Gas owner Centrica is thought to be working in partnership with another firm, possibly EDF. It may take a 25% stake in a joint venture, in return for guaranteed supply to feed its British Gas retail operation.

EDF already operates 19 nuclear sites in France, where it supplies more than 80% of the country's power needs. The group also has extensive operations across Europe, with UK arm EDF Energy boasting 5.1 million gas and electricity customers.

British Energy shares rose 2% today, reversing falls seen in recent days following speculation about limited interest in the power provider.

British Energy operates all eight of Britain's nuclear power stations and should play a major role in the proposed development of the next generation of nuclear power supply.

It said in March it had received takeover approaches, reportedly prompting due diligence interest from five parties in all. The UK Government is considering the future of its 36% stake in the firm, having sold a 25% stake in the company last year for £2.08 billion.

British Energy has 6,000 staff and produces around one-sixth of the UK's electricity. Its eight nuclear power stations are Dungeness B in Kent, Hartlepool, Heysham 1 and 2 in Lancashire, Hinkley Point B in Somerset, Hunterston B in Ayrshire, Sizewell B in Suffolk and Torness in East Lothian.