CNOOC yesterday reaffirmed claims it can save 'several thousand jobs' at United States acquisition target Unocal Corp, after rival bidder Chevron Corp offered promotions to 25 senior Unocal executives to keep their loyalty. About 20 of these executives had accepted the offer, which would leave them in charge of some of the enlarged company's biggest oil and gas producing units, Chevron spokesman Donald Campbell was quoted by Bloomberg as saying. CNOOC faces an uphill battle to persuade Unocal's management to consider its US$18.5 billion all-cash takeover offer. Chevron's US$16.2 billion cash-shares proposal has already been accepted by Unocal's board and approved by the Securities Exchange Commission and the Federal Trade Commission The mainland oil firm's bid has encountered stiff political opposition in the US Congress, which passed a resolution on Thursday calling on the Bush administration to review CNOOC's bid, citing national security threats. Unocal shareholders will vote on Chevron's offer on August 10, allowing little time for to CNOOC to lobby Chevron's management. CNOOC has promised to retain 'substantially all Unocal employees' after its proposed merger. Chevron chairman David O'Reilley reportedly said in April that its merger with Unocal could save US$325 million annually from operating efficiencies, part of which would come from an unspecified number of lay-offs in the US. It has about 6,000 employees. 'Unocal has great people ... that is why we will save several thousand jobs that Chevron will lose,' a CNOOC spokesman told the South China Morning Post. 'We have also said we will keep US oil in the US [and] increase production. 'We remain very optimistic for our merger proposal. We have a clearly superior offer and are expecting a full and fair review of our deal in the [review] process.'