COP21

Ratifying the agreement fits with Beijing's domestic political agenda of being seen to make efforts to clean up

'Signing is good, ratifying is better' Hollande quipped at the Elysee Palace ceremony

The ceremony will be attended by more than 165 governments, largest ever one-day signing of an international agreement

The deal to slow climate change is set to be signed by more than 165 countries at the United Nations

UN's climate science panel announce it will deliver a "special report" in 2018