Mexico has ruled out possibilities of any new treaty at Cancun but hoped to adopt a set of broad decisions within the ambit of Kyoto Protocol towards tackling climate change threats.Minister of Foreign Affairs of Mexico and Chairperson of the Conference of Parties-16 meeting at Cancun, Patricia Espinosa told reporters in New Delhi that Mexico as a host country want to ensure that talks are transparent, open and inclusive so that everybody's views and concerns are taken into account. On her meeting with Foreign Minister S M Krishna, she said issues like energy accessibility and efficiencies were discussed within the framework of climate change. On India's possible role at the crucial climate summit, Espinosa said that India has a key role to play as it is a big economy and emitter and can take a lead in addressing various multilateral agenda.