Orrick Herrington & Sutcliffe and Slaughter and May are advising as talks continue between Centrica and North Sea gas producer Venture Production.
British Gas owner Centrica increased its stake in Venture to 29.9 per cent after Venture rejected an 845p per share hostile takeover bid.
Centrica is reported to be considering making a £1.1bn bid for the rest of the company. Orrick corporate partner Hilary Winter is representing longstanding client Venture, having advised Centrica on buying a 22.3 per cent stake in Venture earlier this year. Panel firm Slaughters corporate partners Charles Randell and John Papanichola are leading for Centrica.