The chief executives of 10 of the world's biggest oil and gas companies have pledged support for an "effective" deal to fight global warming at a Paris conference next month.

In a statement Friday, the CEOs of BP, Shell, Saudi Aramco, Total, Repsol, Statoil, Eni, Petroelos Mexicanos, Reliance Industries and BG Group said they recognize greenhouse gas emissions trends are inconsistent with the ambition to keep warming below a level many consider dangerous.

Burning coal, oil and gas for energy is a key emissions source.

The companies offered to help by reducing flaring and methane emissions from oil and gas operations. They also called for replacing coal with cleaner-burning natural gas in power generation.

Greenpeace said the companies' offer "contains nothing meaningful" and accused them of undermining effective climate action.