Saudi Arabian Oil Co., or Aramco, will invest as much as $90 billion between 2007 and 2012 as the world's largest oil company by production plans to boost crude oil production capacity by almost a third and domestic refining capacity by about 86%, a company official said Tuesday.

State-owned Saudi Aramco will spend $39 billion on joint venture projects, while $51 billion will be invested in its own projects, Nabilah Al Tunisi, manager at Aramco's project support-and-controls department, told a Dubai conference.

The largest part of Aramco's own capital expenditure program, about $31 billion, will be spent on expanding crude production capacity by 2.95 million barrels a day to 12.2 million b/d by 2012, Al Tunisia said.

"This is the largest increase in crude production in Aramco's history," she said.

The remainder of the expenditure program, $20 billion, will flow into the development of natural gas, natural gas liquids and ethane resources, and into refining, exploration, shipping and support, Al Tunisia said.

Aramco's investments will make Saudi Arabia the home of the world's fifth largest refining capacity by 2012, with capacity to process 3.9 million barrels a day of crude, Al Tunisia said.

Saudi Arabia, flush with cash from four years of high oil prices, is spending billions of dollars on expanding its oil and gas infrastructure to meet rising global energy demand, in particular from fast-growing economies such as China and India, and to support hydrocarbon-based industries including petrochemicals to diversify the local economy and create jobs for a growing local population.

The next oil field to come on stream will be Khursaniya by the end of the year, while the largest capacity addition will come from the Khurais field development, which will add 1.2 million b/d by 2010, according to Al Tunisia.

Aramco's worldwide refining capacity will increase by more than a third to 6.5 million barrels in the next five years, which will include the Motiva refinery expansion in the U.S., Al Tunisia said.

Investments into joint venture projects include the Petro Rabigh and Ras Tanura integrated refining and petrochemical complexes, and new export refineries in Yanbu at the Red Sea, and in Jubail, located on the Persian Gulf, that will meet product specifications in markets with stringent environmental regulations such as the U.S. and Europe, she added.

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