Saudi Aramco has asked interested companies to submit cheaper offers to build parts of a complex to supply energy to an oil refinery at Jizan, industry sources said.

A total of 14 companies bid in October for four packages to build elements of a 2,400 megawatt (MW) integrated gasification combined cycle (IGCC) plant at the refinery.

The bids were higher than the state-run oil giant had hoped for, so it is now inviting lower-cost bids for three of the four packages, one source said.

"The original bid price exceeded the budget so they are trying to find ways to shrink the cost," said a second source familiar with the matter.

Saudi Aramco declined to comment.

Aramco has re-tendered three of the four construction packages, as it is in talks with China's Sepco III over the power plant package, sources said.

The plant will supply the 400,000 barrel per day oil refinery and other consumers around the industrial port on the Red Sea coast.

Construction of the refinery has not started. It will be the last of a trio of new 400,000 bpd refineries in Saudi Arabia between 2013 and 2018.

The refinery will process heavy and medium crude oil into around 75,000 bpd of gasoline and 250,000 bpd of ultra-low-sulphur diesel. - Reuters