India opposed using the Montreal Protocol ozone-protection treaty to restrict powerful greenhouse gases called hydrofluorocarbons, pouring cold water on efforts by the U.S. and the European Union.

“It's honestly beyond me how a non-ozone depleting substance like HFCs can be taken into the Montreal Protocol, which deals only with ozone-depleting substances,” Indian Environment Minister Jayanthi Natarajan told envoys at United Nations climate talks in Warsaw today. “We are unable to fathom what prevents addressing this issue” under the UN Framework Convention on Climate Change.

U.S. and EU envoys have suggested using the ozone treaty to pare back the gases. That would bypass slow-moving UN climate talks, which often deadlock on unrelated issues. The gases are made by companies including Honeywell International Inc. and DuPont Co. in a $US4 billion ($4.4 billion) global refrigerant industry.

Tackling HFCs is important because the gases are up to 11,700 more powerful agents of global warming than carbon dioxide, according to the UN. Phasing them down has the potential to slash 90 billion tons of greenhouse gases through 2050, said Todd Stern, the U.S. special envoy on climate change. That's almost two years of greenhouse-gas output at current levels.

“The Montreal Protocol is made for this kind of task,” Stern said today. “It's what it does, It phases down industrial chemicals. Let's start making progress here instead of making excuses.”