The Department for Trade and Industry is expected to raise some £2.2 billion from the sale, to be put towards its Nuclear Liabilities Fund.
British Energy, in which the government acquired a 64 per cent stake back in 2002, has seen an upturn in fortunes over recent years and today posted profits of £1.2 billion for the year to March.
This was a 44 per cent increase in underlying profit and the first dividend for the firm since government intervention five years ago.
The company operates eight nuclear power stations and one coal plant with 6,000 staff and is able to supply around one-fifth of the UK's energy.
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