New York, Sep 24 (DPA) British Prime Minister Gordon Brown Wednesday urged world leaders to work towards a 'global society' and improve cooperation on curbing global warming, nuclear proliferation, terrorism and economic recovery.

Brown said the global economic crisis of the last year had demonstrated how governments can work together to avert disaster, but he warned that cooperation was lacking on a whole host of other global issues.

If world powers could renew that cooperation, Brown said, 'I believe we are in the business ... of creating a truly global society.'

Brown said the world was in danger of reversing decades of success in limiting nuclear proliferation and said major powers should be prepared to adopt stiffer sanctions on Iran and North Korea.

'Let their be no ambiguity: Iran and North Korea must now know that the world will be even tougher on nonproliferation,' Brown said.

He proposed a 'grand bargain' in which existing nuclear states would offer access to civilian power to non-nuclear states.

Brown called on Western powers not to give up on the war in Afghanistan, warning that Al Qaeda and other terrorist groups would otherwise return to the region.