'But obviously negotiations are ongoing, but I think the secretary felt it was a constructive conversation.'

At the same time, Crowley also reiterated the US stand that to successfully address the challenge of climate change 'meaningful steps' would have to be taken 'both by developed countries, like the United States, and emerging countries, like India and China'.

'But obviously, as we've made clear ... the US and other developed countries have a special responsibility because up until now we have in fact generated many of the greenhouse gases that have brought us to where we are.'

'But we also recognize, going forward, that something like 80 percent of the greenhouse gases that will be emitted in the future will come from countries like India and China,' Crowley said.

So 'ultimately, for us to successfully address the challenge of climate change in the world, you have to have meaningful steps done both by developed countries, like the United States, and emerging countries, like India and China.'

(Arun Kumar can be contacted at arun.kumar@ians.in)