Asia's largest oil refiner, Sinopec Corp, and the world's biggest chemicals maker by market value, Saudi Basic Industries Corp (Sabic), received regulatory approval from China to develop a previously agreed-to project into a full-fledged venture in Tianjin.

The $3-billion complex, to be operational in September this year, will have an annual capacity of 3.2 million tons of petrochemicals, including ethylene, the primary building block for petrochemicals, and all other downstream products, Sinopec said on its website.

The target production capacity of this 50-50 joint venture was first set at 4 million tons in June 2008.