World nations have no choice but to join forces to stop global warming, but achieving a legally binding treaty this year should not be the only focus, AP quoted the new U.N. climate chief as saying today. Christiana Figueres said that «governments will meet this challenge, for the simple reason that humanity must meet this challenge.» «We just don't have another option,» said Figueres, who replaces Yvo de Boer next month as head of the U.N. Framework Convention on Climate Change. Her comments came as another two-week climate meeting in Bonn was nearing its end without much visible progress toward reaching a comprehensive global climate deal. These were the first full-fledged climate negotiations since the disappointing December summit in Copenhagen which came up only with a nonbinding political declaration. The Bonn meeting is to pave the way to the next U.N. climate summit in Cancun, Mexico, at the end of the year which some countries hope will provide a breakthrough. Figueres did not say if she thinks a deal is possible in Cancun. «It is too simplistic to focus on: Do we have a legally binding treaty and if so by when,» she said. Even if a treaty is agreed on, «I don't believe that we will ever have a final agreement on climate, certainly not in my lifetime.» Her predecessor de Boer, who had struck a pessimistic note on Monday saying in his final speech to Bonn delegates that he had given up on ambitious short-term climate goals, said he was hopeful for the long term. «We are on a long journey to address climate change,» de Boer said. While at this point the goal to limit global warming to 2 degrees Celsius (3.6 degrees Fahrenheit) is in danger, the issue «takes more than one round of negotiations,» he said. «I am confident that in Cancun you will not only try but succeed» in setting up a stucture for the fight against climate change, he said. Scientists say industrial countries need to cut their emissions by 25-40 percent as compared to 1990 levels by 2020 and by 80 percent by 2050. So far, pledges to cut greenhouse gases only add up to about 13-14 percent by 2020. Nonetheless, Figueres said industrial countries could still meet the tough cuts needed, as their governments acknowledge the gap and are working on improvements. «I am also confident that we'll see technology breakthroughs to also fill this gap,» she said. Alden Meyer, of the U.S.-based group Union of Concerned Scientists, said expectations of Figueres were high. «She has the personality and she has skills» to facilitate progress, Meyer said, noting Figueres' 15 years as a Costa Rican climate negotiator. Figueres said no one should mistake her for naive in her optimistic outlook. «I have been through the ups and downs of the process,» she said. «I am fully aware that we are not there yet. This is a long-term process.» She insisted the Copenhagen summit had yielded some positive results, despite ending with a nonbinding political declaration that disappointed many. Specifically, she noted rich countries' commitments to provide billions in aid to poorer nations as well as voluntary pledges for emissions reductions. The upcoming Cancun summit will be the «time for delivery» on these promises, she said. «I am convinced that Cancun is going to be very productive, that it is going to be successful.» In Bonn, however, delegates from 185 nations seemed caught up in technical questions without making much headway on the crunch issues, said May Boeve of the climate group 350.org.