Rio Tinto Chairman Simon Thompson asked shareholders to reject a resolution in the upcoming annual general meeting in May that calls for the company to report its direct emissions and those of its customers in greater detail.

The rule change would have Rio Tinto set out plans in its annual reporting, starting in 2020, to limit global warming, including targets to reduce a variety of greenhouse gas emissions.

The company said March 15 that it is conducting detailed engineering, economic and policy analysis on an asset-by-asset basis to create reduction targets for emissions from the company's own sources as well as indirect emissions from purchased energy. The new targets would replace the existing ones expiring in 2020.

However, Thompson said setting targets for all emissions in the company's value chain, called scope 3 emissions, is primarily in the hands of its customers in China. "Options exist for the reduction of these emissions, but the speed, economic viability and ultimate deployment of these technologies lie within the control of our customers, not Rio Tinto."

He added that the company can provide scenarios for the speed and effectiveness of reduction measures instead of setting specific targets.

Rio Tinto's current analysis to set new targets uses a less than 2°C scenario, reflecting the International Energy Agency's sustainable development target rather than the unofficial Paris agreement on climate change target of 1.5°C, as set out in the resolution.

Thompson said the company will continue to assess scenarios in line with International Energy Agency's ongoing work.

Recently, Rio Tinto CEO Jean-Sébastien Jacques said the miner is in discussion to move into the next phase of an agreement with Apple Inc. as it plans to transition its aluminum business to tap a low-carbon economy.