BHP Billiton has won a contest to partner with Pemex in a joint oil venture to develop a deepwater field in untapped Gulf waters.
According to reports, a local unit of BHP Billiton won the rights to tie-up with Pemex on its light oil Trion field.
It is less than 50 miles from the US Mexico maritime border.
BHP outbid BP for the share, with a $624million offer to complement its royalty bid.