The CNOOC Ltd counter-offer amounts to $67 in cash per Unocal share.
Fu Chengyu, the Beijing giant's chief executive, said: "This friendly, all-cash proposal is a superior offer for Unocal shareholders.
"The deal is fully financed, subject to customary closing conditions, and priced in line with market values for comparable businesses. We hope to be able to enter into a dialogue with Unocal soon and reach agreement on a consensual transaction."
CNOOC
