Leading North Sea independent Serica Energy has rejected a £1.04 billion takeover bid from smaller rival Kistos.

Details of the proposal were made public this morning by Kistos, which made a cash-and-stock offer of 382p per share representing a 25 per cent premium to Serica's closing price on July 11. The offer included 0.2932 new Kistos shares and 246p cash for each share in Serica.

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"While Serica has stated that its board 'can see industrial logic in combining the portfolios of the two companies', the proposed combination has been rejected by the board of Serica," Kistos said in a statement.

A counter-offer by Serica was also rejected by Kistos, under which it proposed paying 90p and 1.29 new Serica shares for each Kistos share. Kistos - which has a 20% stake in the TotalEnergies West of Shetland offhosre fields, plus assets in the Dutch North Sea - said the offer was "at the wrong price, with the wrong mix of stock and cash".

Formed in 2004 and headquartered in London, Serica produces roughly 5% of the UK's gas supplies.