Saudi Aramco said its oil refinery joint venture with France's Total will double capital investment to SR7.12 billion ($1.9 billion) at Jubail, the largest industrial city in the region.

Saudi Aramco Total Refinery and Petrochemicals Company (Satorp) will increase spend at the site from SR3.56 billion in the first-quarter of 2013, according to a statement on the Saudi bourse website.

State-owned Aramco holds a 62.5 per cent stake in the project, with Total holding the remaining 37.5 per cent stake. The capital increase will be on a pro-rata basis, the statement said.

In 2010, the joint-venture firm said it had raised $8.5 billion towards the $12.8 billion project and issued in 2011 SR3.75 billion Islamic bonds to help pay for it.

The refinery, whose construction is close to completion is part of Saudi Arabia's drive to boost crude refining capacity and would process heavy crude from Aramco's giant 900,000 barrels per day Manifa oilfield.

Aramco and Total have already started testing some units at the 400,000 barrels per day refinery, due to be fully operational in the third quarter of 2013.

The refinery would produce around 190,000 bpd of diesel, around 90,000 bpd of gasoline and 50,000 bpd of kerosene as well as petrochemicals.-Reuters