UN Secretary-General Ban-Ki Moon has warned on Monday that inaction to tackle climate change could prove the costliest action of all and said there was the need for unprecedented action and leadership to address the challenge head-on.The change, he said, was a serious threat to development everywhere and that its adverse impacts could undo much of the investment made to achieve the Millennium Development Goals (MDG's)."But it is not a zero-sum game. By being creative, we can reduce emissions while promoting economic growth", he said, in an address at a high-level meeting held at the UN Headquarters in New York.President John Agyekum Kufuor was among the 20 world leaders who participated.The UN, asked that national action must be at the centre of the response to the change - with industrialized countries, whose per capita emissions remain unacceptably high, taking the lead. Mr. Ban-Ki Moon, however, acknowledged that given the nature and magnitude of the challenge, national action alone was not sufficient."No nation can address this challenge on its own. No region can insulate itself from these climate changes. That is why we need to confront climate change within a global framework, one that guarantees the highest level of international cooperation."This, he said, was the kind of global challenge that the UN was best suited to address, adding that the meeting was an opportunity to infuse the process with political momentum."We need to set the stage for a comprehensive agreement that tackles climate change on all fronts. We hold the future in our hands. Together, we must ensure that our grandchildren will not have to ask why we failed to do the right thing, and left them to suffer the consequences."Source: GNA