Thai state firm PTTEP is expanding its modest Gulf footprint. It aims to use the partnerships that come with its latest deal as a springboard to further expansion.

Thailand’s PTTEP is emulating its regional compatriots in betting on Mideast upstream assets. The state firm returned to the Gulf in January, snagging two exploration blocks in Abu Dhabi alongside Italy’s Eni, and is now broadening its footprint with the purchase of the storied, albeit minor, firm Partex.

PTTEP...