MUMBAI, Aug 12 — The head of India’s Reliance said today that it has agreed to sell a 20 per cent stake in its oil refinery and chemical unit to Saudi Aramco in a deal worth US$15 billion.

“This is the biggest foreign investment in the history of Reliance and also amongst the largest foreign investments ever in India,” India’s richest man Mukesh Ambani said at the company’s annual general meeting in Mumbai.

The preliminary agreement is based on a valuation of US$75 billion for Reliance’s Oil to Chemicals (O2C) division comprising the refining, petrochemicals and fuels marketing businesses of the Indian firm, according to a Reliance statement. — AFP