BANGKOK — Top climate brokers from more than 160 nations launched a new round of talks in Bangkok on Monday aimed at setting out a plan for the most ambitious treaty yet for battling global warming. Opening the five-day meeting with a video message, UN Secretary General Ban Ki-moon urged countries to work together to find a solution to climate change. ‘The state of our planet requires you to be ambitious in what you aim for and in how hard you work to reach agreement,’ he said. Meeting for the first time since marathon negotiations in Bali, Indonesia late last year, delegates at the UN-led talks will thrash out a plan toward a new global pact on slashing greenhouse gas emissions and battling climate change. The deadline for reaching a new accord is at the end of 2009. Individual countries would then need to ratify it before their current commitments under the existing Kyoto Protocol to cut emissions expire in 2012. Although rich and poor nations now generally agree that the world must take action to halt climate change, they are divided on how to go about it. The United States, which never ratified […]