The contract for an estimated $4bn package on Abu Dhabi’s offshore Upper Zakum oil field development is not expected to be awarded until early 2013, according to industry sources.

The scheme’s operator, Zakum Development Company (Zadco), received five commercial bids for the engineering, procurement and construction (EPC) contract, which covers the package known as EPC-2.

South Korean contractors Hyundai Heavy Industries (HHI) and Samsung Engineering emerged as the two frontrunners to win the deal, having submitted the lowest commercial proposals, three companies bidding on the contract told MEED in late September.

The contract, which was expected to be the largest single oil and gas EPC deal in the Middle East in 2012, is now expected to be awarded during the first quarter of 2013. No specific reason has been given to the extended period before the contract award.

EPC-2, which includes the construction of crude processing trains on four new artificial islands, is part of Zadco’s plans to increase the field’s capacity to 750,000 barrels a day (b/d) from 500,000.

In July, Zadco awarded the $800m EPC-1 first Upper Zakum package – covering the offshore section of the development – to a consortium of Technip and NPCC. Zadco is a joint venture of state-owned Abu Dhabi National Oil Company (Adnoc), US oil major ExxonMobil and Japan Oil Development Company (Jodco).