A key element of the international plan to address climate change is in jeopardy after several of the most powerful nations failed to confirm a previous commitment to halve greenhouse gas emissions by 2050. The Asia-Pacific Economic Co-operation (Apec) forum, which includes the US, China, Japan and Russia, deleted the commitment from the final version of the official communiqué issued after a two-day meeting in Singapore. The commitment had been made by G8 leaders at L’Aquila in Italy in July and the decision to remove it is a retrograde step. The resolve of world leaders to take firm action on climate change appears to be weakening, with President Obama confirming that there would be no legally binding deal at the UN summit in Copenhagen next month.