To foray into Indian oil and gas sector, Saudi Aramco, world's biggest oil producer, plans to buy up to 30 per cent stake in ONGC Petro additions Ltd with a lead role in the Indian government-owned giant petrochemicals project in Gujarat.    

ONGC is the lead promoter of OPaL while GAIL and Gujarat State Petroleum Corp (GSPC) are the other partners of the joint venture.    

Currently, ONGC owns 26 per cent while GAIL has 19 per cent and GSPC per cent. For India, investment in the Rs 19,500-crore project by the Saudi behemoth will come as a shot in the arm for the business climate, which has suffered as the rupee has tumbled, markets have crashed and foreign investors are jittery.    

On its part, Aramco also aspires to become the world leader in chemicals and is partnering Dow Chemicals in a $20-billion venture to build the world's biggest petrochemicals complex in the east of the kingdom. It partners Exxon, Total and other firms in refining and chemicals ventures too.