Companies including Shell, Total, Statoil, Eni and BG Group, as well as governments including Russia, Angola, France, Norway and Kazakhstan, have all signed the document. Together, they represent about 44% of all routine gas flaring in the world.

"Flaring at oil production sites around the globe burns approximately 140 billion cubic metres of natural gas annually, causing more than 300 million tonnes of carbon dioxide to be emitted to the atmosphere," said Anita George, senior director of the World Bank Group's energy and extractive industries global practice.

"If