At least 10 contractors are expected to file construction bids to the state-run Saudi Aramco by 5 December to build a $250m bulk plant at Wasea, southeast of Riyadh.

A Saudi-based contractor close to the project says at least 10 of the 20 prequalified companies are expected to proceed with a bid.

In November, Aramco delayed construction bids to 5 December from the original 14 November deadline.

Aramco has set a deadline of 29 February 2012 for the successful contractor to complete the plant.

The plant will handle an increase in petrol, diesel and fuel oil supplies to the region, with capacity to handle 185,000 barrels a day of oil. Saudi firm Dar al-Riyadh is the design contractor on the project.

The winning contractor will build tanks, petrol and diesel-loading pumps, as well as substations, and carry out civil engineering and structural work.