While India is also growing fast in importance, it should be absolutely clear that it is the two largest CO2 emitters most of all, my own country, that will need to make the boldest moves, or stand accountable before history for their failure to act.

"Both countries should stop using the other's behaviour as an excuse for stalemate and instead develop an agenda for mutual survival in a shared global environment," Mr Gore said at a lavish ceremony in the Oslo city hall.