The UN conference on climate change is moving towards its climax as environment ministers from some 100 countries meet in Montreal.It is the biggest climate change summit since Kyoto was signed eight years ago. The goal of the summit which ends on Friday is to draw the United States and other big polluters into Kyoto-style agreements to reduce greenhouse gas emissions after the protocol runs out in 2012. But the US, which produces 25 percent of the world’s greenhouse gases, has made clear it opposes talks on extending limits on its emissions. The conference has drawn thousands of environmental activists. Delegates will engage in bilateral talks on the margins of the summit led by Canadian environment minister Stephane Dion. Backers of Kyoto, such as Canada, the EU and Japan, are lobbying for an extension of Kyoto. Some analysts believe it is unlikely delegates will succeed in setting a date for agreeing on a successor for the protocol.