COP21: What happens if climate conference fails?

Negotiators from 196 countries are trying to reach a deal at the climate change conference in Paris to curb global warming.

A draft deal was reached last week but key issues still remain, including a long-term goal to reduce emissions from burning coal, oil and gas.

BBC environment correspondent Matt McGrath asks what happens if the conference fails to reach an agreement.

Produced by Marcus Thompson and Jean-Li Lee