The Paris conference will be attended by at least 80 world leaders including China’s President Xi Jinping and US President Barack Obama.

It seeks to unite all the world’s nations in a single agreement on tackling climate change, with the goal of capping warming at two degrees Celsius (3.6 degrees Fahrenheit) over pre-Industrial Revolution levels.

With this declaration, we have set up conditions which open the way to success and I am minded to believe that an agreement is now possible.

Each signatory’s progress should be reviewed every five years, China and France said in a joint statement, to “reinforce mutual confidence and promote efficient implementation”. They gave no details.