Fourth quarter tonnage was 16% higher than the same quarter of 2014 due to the longwall changeover at Kestrel in 2014.

Rio Tinto CEO Sam Walsh said: “Against a challenging market backdrop for the industry, Rio Tinto remains focused on operating and commercial excellence to leverage the low-cost position of our Tier 1 asset base.

“In 2015, we delivered efficient production, meeting our targets across all of our major products, while rigorously controlling our cost base. We will continue to focus on disciplined management of costs and capital to maximise cash flow generation throughout 2016.”

The future of Kestrel could not be guaranteed if an extension to continue production for another 20 years is not granted, the company has warned the Federal government last year in a submission.

The company volunteered this information to the Federal government despite it receiving approval beforehand because of changes to the EPBC Act in regard to water tables.

Rio is seeking a mining lease for the Kestrel extension, which is expected it to produce about 5.7 million tonnes a year over the next 20 years.

Rio Tinto’s share of hard coking and thermal coal production was in line with 2015 guidance, while semi-soft coking coal production was seven per cent above the top end of the guidance range due to mine sequencing.

Semi-soft coking coal production was 14 per cent higher than 2014, and nine per cent higher in the fourth quarter than in the same quarter of 2014, reflecting mine production sequencing at Hunter Valley Operations.

In 2016, Rio Tinto’s share of production is expected to be 7 to 8Mt of hard coking coal, 3.3 to 3.9 million tonnes of semi-soft coking coal and 16 to 17Mt of thermal coal.

Thermal coal guidance includes a contribution from Bengalla up to the expected date of divestment during the first quarter of 2016.