Bankers close to the deal tell MEED that JBIC is offering to support bids from the consortiums led by Sumitomo Corporation and Marubeni Corporation, both from Japan. If either bidder wins, it will be the largest ever loan made by JBIC on a Saudi project.

With a $3bn JBIC loan, banks will be expected to provide an additional $2bn in financing for the project. At least half of this will be denominated in Saudi riyals.

JBIC lent $2.5bn to the Petro Rabigh project in 2006, and $3bn to Abu Dhabi National Oil Company in December 2007.

Although a winning bidder has not been officially selected for the project, the Sumitomo consortium, which also has financial support from Royal Bank of Scotland, Citigroup, Sumitomo Mitsui Banking Corporation, Mizuho and Bank of Tokyo-Mitsubishi, is the favourite, according to sources close to the project.

Sumitomo has declared itself the preferred bidder. However, Water & Electricity Company denied the claim in early July.

JBIC is also supporting the bid by Marubeni and Belgium's Suez Energy International, which has additional bank support from National Commercial Bank, Banque Saudi Fransi, Calyon and Standard Chartered Bank.

A third bid was tabled by the local Acwa Power Projects with Korean Electric Power Corporation.