Aluminum Corp of China (Chalco), China's top aluminium producer, will invest 1.2 billion dollars in a joint venture in Saudi Arabia, the commerce ministry said Monday.

Under an agreement signed Saturday, Chalco will take a 40 percent stake in the three billion dollar smelter, which includes investment from Malaysia's MMC and Saudi Binladin Group of Saudi Arabia, the ministry said in a statement.

The ministry did not provide a complete breakdown of venture's equity structure but said it was the largest Chinese investment in Saudi Arabia so far.

The venture, located in Jazan in southwest Saudi Arabia, will have an annual output of one million tonnes of aluminium. Some of the products will be exported to China, it said.

Construction on the project is slated to start next year and will be completed by Chalco in three phases using Chinese technology and equipment, it added.

Chalco will also manage the venture, which was first announced in October.