Unocal Supported Chevron, Not CNOOC

US oil major ChevronTexaco, fighting for US oil firm Unocal, has increased its offer and won the support of Unocal's board.

Chevron has now offered a $63 per share bid in stocks and cash, up from an earlier bid of $60.

That values Unocal at $17.1bn, less than the $18.5bn all-cash bid put forward by Chinese oil company CNOOC.

The Chinese firm CNOOC repeated its efforts to reassure politicians that its takeover would not jeopardize jobs or prove to be a security risk, and has given assurances that it would sell some assets and leave others in US hands.