French President Francois Hollande warned on Friday that a major international summit to be held this month in Brazil aimed at breaking years of deadlock on pressing environmental issues may fail. Hollande, who will attend the summit, said there was a \"risk of division between developed countries, emerging countries, poor countries, the risk of failure because there may be other pressing matters. \"The world is today turned towards the economic crisis, the financial crisis, and is worried about a certain number of conflicts, such as Syria\", which means \"one might easily turn away from what is however the top priority, the environment,\" he said. One hundred world leaders are set to attend the UN Conference on Sustainable Development on June 20-22 in Rio de Janeiro. The summit is taking on the vast challenge of transforming environmental, social and economic policy to cope with a world population of more than seven billion that is exhausting dwindling resources and straining cities to the limit. But UN leader Ban Ki-moon and specialist groups have accused governments of putting national interests before the common good in months of agonizing negotiations before the Rio event to mark the 20th anniversary of the Earth summit in the same city.