Rio Tinto has achieved its goal of producing more than 250 million tonnes of iron ore in 2012, after a strong three months for the company at its Pilbara operations.

Rio's final iron ore production tally of 253 million tonnes was achieved by producing 66 million tonnes in the three months to December 31.

That figure includes some volumes that are owned by joint venture partners, such as Gina Rinehart's Hancock Prospecting.

Rio's share of annual iron ore production was 199 million tonnes.

The record iron ore result was contained in Rio's December quarter results which were published to market shortly after 3pm.

Rio shares recovered slightly on the report and were down just 4 cents, or 0.1 per cent, at $65.98 in late trade, after earlier falling as much as 0.7 per cent.

Despite the good news, Rio failed to meet its annual targets for amounts of copper mined and refined.

The miner also said its aluminium division produced 10 per cent less primary metal in 2012 versus 2011 due to a labour dispute.

The company said it would also make a decision later this month on whether to mothball the Gove alumina refinery in Australia.

Iron ore prices have soared more than 80 per cent since September as Chinese steel mills - the single biggest buyers of seaborne-traded ore - returned to the market on signs of a recovery in the Chinese economy.

Benchmark prices hit a 15-month high of $US158.50 a tonne last week, as China's iron ore imports topped 70 million tonnes for the first time in December helped by a resurgent economy and a cold snap that cut local production.

Rio's most important task for 2013 will be to successfully bring its Mongolian copper and gold mine - Oyu Tolgoi - into production, and today's announcement reveals further progress on that goal.

Rio confirmed that first ore was processed through the concentrator on January 2, meaning that production of concentrate should be due around the start of February.

The mine should be reaching commercial production by June, and Rio revealed that 25 per cent of the concentrate produced would go to the Chinese province known as "Inner Mongolia".

As previously advised, Rio said it would decide in late January whether to continue operating the Gove alumina refinery.