Global climate talks are progressing too slowly and too many countries are demanding action from others rather than acting by themselves, Sweden's Environment Minister Andreas Carlgren said.
Sweden holds the rotating Presidency of the EU for the rest of the year, during which time global climate talks, culminating in a conference in Copenhagen in December, are supposed to agree on a successor to the Kyoto Protocol.
"The negotiations are too slow because too many are pointing at others and requesting them to do more," Mr Carlgren told a briefing in Beijing.
The EU had no "plan B" beyond Copenhagen, he said.
"That's why the EU has said we'll reduce emissions by 20 per cent regardless.
"So if other parties would start in this way, moving forward, we would achieve great things in Copenhagen," said Mr Carlgren, adding that he had had a frank exchange with Chinese officials.
China has overtaken the US as the world's biggest emitter of greenhouse gases because of its rapidly expanding economy and dependence on coal, the dirtiest fossil fuel.
Developing nations led by China and India say rich countries should aim for cuts in emissions, mainly from burning fossil fuels, of at least 40 per cent below 1990 levels by 2020.
Last week, leaders at the 17-member Major Economies Forum in Italy agreed that global temperature rises should be limited to two degrees Celsius above pre-industrial levels, but also said developing nations such as China and India should commit to meaningful carbon reduction targets of their own after 2012.
Mr Carlgren said the EU agreed that developing countries "should present mid-term targets that would lead to meaningful deviation from business as usual."
That would mean a reduction in CO2 emissions in India and China of 15-30 per cent compared to current "business as usual" projections, he said.
US Energy Secretary Steven Chu and Commerce Secretary Gary Locke are visiting China this week to press Chinese leaders to join stepped-up efforts to fight global warming. The trip also sets the stage for a visit by President Barack Obama to China later this year that many environmental experts hope will focus on the need for joint US-China action before the Copenhagen meeting.
The US signed but never ratified the Kyoto Protocol, becoming the only major developed nation to remain outside the treaty.
Many in Washington opposed a pact that did not set a ceiling for future emissions growth by China and other big developing powers.
Since winning last year's election, Mr Obama has made fighting climate change a major policy focus and wants to introduce a cap-and-trade system to curb carbon emissions.
Kyoto held developed countries to a higher standard than developing countries, since the former were committed to caps on emissions, while the latter had no such obligation.