"BEIJING -- Top U.S. officials on Wednesday left open the possibility that China might not have to accept a hard cap on its greenhouse gas emissions under a new global climate change treaty.
'Right now, our purpose is really to convey the seriousness of this issue and the need for U.S.-China leadership,' U.S. Commerce Secretary Gary Locke told Reuters on a trip to China to boost cooperation on energy conservation and cleaner fuels.
'What the ultimate mechanism may be is to be decided at Copenhagen. But it is something that can not be shirked or delayed,' Locke said.
Countries are scheduled to meet in Copenhagen in December to agree a new climate treaty to replace the Kyoto Protocol -- which expires in 2012 -- to reduce carbon dioxide (CO2) and other emissions blamed for raising global temperatures.
Scientists say major emissions cuts are needed to prevent dramatic climate changes that could cause more droughts, flooding and disease, and cause ocean levels to rise.
In a separate interview, U.S. Energy Secretary Steven Chu said he would leave it 'to the diplomats' to figure out whether China will be required to cap emissions as part of the new pact."