The chief executive of the world's largest miner, BHP Billiton, has backed Prime Minister Tony Abbott's decision to keep climate change off this year's G20 agenda, despite concerns Australia is increasingly viewed as being disengaged from the international climate debate.

In the same week that United States president Barack Obama pledged to slash carbon emissions from power plants by 30 per cent on 2005 levels, and China flagged an unprecedented absolute cap on emissions, Mr Abbott signalled he would pass on the opportunity to use Australia's leadership role as host of the G20 to focus on climate change – arguing the November summit in Brisbane was primarily an "economic meeting" to discuss matters of finance and trade.

"If you try and use [the G20] to solve all the problems of the world, you'll solve none.": BHP chief Andrew Mackenzie. Credit:Reuters

"I don't think that's a backward step," BHP chief executive Andrew Mackenzie told reporters in Beijing, where he was attending meetings as part of a trade and business advisory panel advising the G20. "I agree with the Australian government with this. If you try and use [the G20] to solve all the problems of the world, you'll solve none. It's better to concentrate on a few things and do them really well."