Centrica, the owner of British Gas, was given a July deadline yesterday to mount a bid for Venture Production, the North Sea gas producer.

The Takeover Panel told Centrica, which has built up a 22 per cent stake in Venture, that it must table a full offer by July 13 or walk away for six months.

In March, Centrica spent £240 million on the stake and confirmed that it was considering making a full cash offer. However, Venture wants more than the 725p that Centrica paid for each share, valuing the company at £1.1 billion. At the time, Mike Wagstaff, Venture’s chief executive, described the approach as “highly opportunistic”.

Centrica is interested in gaining access to Venture’s substantial reserves of North Sea gas to supply its British retail customers, of which there are nearly ten million. The company’s own gas production provides only 29 per cent of its UK requirements, forcing it to buy the remainder on volatile wholesale markets. Acquiring Venture would boost that figure to about 40 per cent and nearly double Centrica’s total reserves base from 238 million to 452 million barrels of oil equivalent. Venture, whose fields lie mainly in the southern part of the North Sea, is drilling another 15 wells this year.

Venture claims that the price at which Centrica had bought its shares valued Venture’s reserves at only $8.80 per barrel, compared with the market price of over $70.

The Takeover Panel said: “Centrica must, by 5pm on July 13, either announce a firm intention to make an offer for Venture . . . or announce that it does not intend to make an offer.”

Last month Centrica signed a joint-venture agreement with EDF, of France, that will involve it taking a 20 per cent share in British Energy, the UK nuclear generator.

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