World leaders meeting in Singapore have said it will not be possible to reach a climate change deal ahead of next month's UN conference in Denmark. However, after a two-day Asia-Pacific Economic Forum summit, they vowed to work towards an "ambitious outcome" in Copenhagen. <br/> <br/>But if feelers coming from interactions among the leaders on the sidelines of the summit are too believed then next month's much-anticipated climate change summit in Copenhagen will also not result in any legal binding agreement for a worldwide global warming treaty. <br/> <br/>The 21-member grouping dropped a target to halve greenhouse gas emissions by 2050, which was outlined in an earlier draft of the joint statement.<br/> <br/>Another highlight of APEC was that the Leaders, including the US and Chinese presidents, agreed to pursue a new strategy for growth after the world's worst economic crisis in decades. They resolved to conclude the Doha round of global trade talks in 2010. <br/> <br/>In a joint declaration, they said they firmly reject all forms of protectionism and reaffirm their commitment to keep markets open and refrain from raising new barriers to investment or to trade in goods and services. They also agreed to keep stimulus spending in place until a recovery was seen.<br/>