Danish environment minister Connie Hedegaard on Friday asked political leaders to press for a climate change treaty at Copenhagan, stepping up pressure before a global climate change conference in the capital of Denmark.

There has not been much progress in negotiations for a new treaty beyond 2012, when the Kyoto Protocol ends.

The protocol talks of differentiated responsibility for rich countries (the traditional polluters) through emission cuts and the developed world (sufferers) through fund transfers.

The rich countries want an end to differentiated responsibility and want advanced developing economies like India and China to agree to emission cuts, which are opposed by the developed world.

Hedegaard said at a climate change conference in Delhi that the Denmark government was mulling calling heads of state at a later stage of the Copenhagen conference to ensure a “fruitful” treaty.

The Prime Minister’s special envoy on climate change, Shyam Saran, sought a collaborative approach to achieve an effective deal at the Copenhagen meet.

“If we say that we are facing an extraordinary challenge that requires extraordinary response, then the least common denominator is not the response that is required,” the country’s chief climate change negotiator said.

India pitched for accelerating deployment and diffusion of green technologies to tackle climate change.