China must play its part in talks to frame a new deal on climate change, French President Nicolas Sarkozy says.
Mr Sarkozy urged Beijing to exert more influence on industry
Speaking at the end of a three-day visit to China, Mr Sarkozy called on Beijing to agree to specific targets for cutting greenhouse gas emissions.
UN talks begin in Bali next week aimed at sealing an accord to replace the Kyoto Protocol, which expires in 2012.
Beijing has argued developed countries should bear the main responsibility for tackling global warming.
Mr Sarkozy appealed to China's authorities to exert "immediate, profound and sustainable" influence on the way it produces goods and consumes energy.
"If we don't fix targets we won't succeed in avoiding catastrophe," he said in a speech to students at Beijing's Tsinghua University.
"We can't have one response for Europe and one for Asia, one for the north and one for the south.
"We must absolutely find a way as industrialised, emerging and developing countries of working together to divide greenhouse emissions in half by 2050."
Earlier, Mr Sarkozy and his Chinese counterpart Hu Jintao released a joint statement on environmental issues.
It said both countries "recognise the importance and the urgency to fight against climate change and to put in place sustainable development".
During his first trip to China as president, Mr Sarkozy has helped to secure 20 billion euros ($30bn; £14.5bn) in business deals for France - including contracts to build two nuclear reactors in China.