Three leading international contracting giants are battling it out for a prized onshore contract from Adnoc Sour Gas for the expansion of its Shah sour gas facility in Abu Dhabi.

The Shah expansion project is a crucial part of state-owned giant Abu Dhabi National Oil Company (Adnoc)'s integrated Gas Master Plan, which seeks to ramp up natural gas supplies to support several industries across the United Arab Emirates.

Adnoc Sour Gas — a joint venture between Adnoc and Occidental Petroleum of the US — last year initiated the tender process for the Shah Gas expansion project.