IVANHOE Mines has unveiled an updated development plan for the big Oyu Tolgoi project in Mongolia that could boost copper production by 50 per cent and gold output by 126 per cent.

Oyu Tolgoi, the world's largest undeveloped copper-gold project, recently got the go-ahead from the Mongolian government when a 50-year investment agreement was finalised. The government holds a 34 per cent stake in the project, with Vancouver-based Ivanhoe owning the remaining 66 per cent stake.

Anglo-Australian miner Rio Tinto owns a 22.4 per cent stake in Ivanhoe and has the right to increase its stake to 46.6 per cent.

Based only on proven and probable reserves, Ivanhoe said it now expects average annual production of 1.2 billion pounds of copper and 650,000 ounces of gold from Oyu Tolgoi for the first 10 years of production.