Incoming EU commissioner for climate action, Denmark's Connie Hedegaard, on Friday criticised Europe's lack of a united voice at the fraught international talks on global warming in Copenhagen.

Hedegaard made the comments during a three-hour grilling at the European parliament over her suitability for the new post.

The former Danish climate and energy minister, who chaired most of the Copenhagen talks before being replaced by her prime minister following criticism of her methods, said she was "disappointed" that the UN meeting last month "did not deliver binding targets" on greenhouse gas emission reductions.

While insisting that "the EU played a tremendously important role in paving the way for change," she decried the lack of a unified European voice.

"Those last hours in Copenhagen. China, India, Japan, Russia, the US, each spoke with one voice, while Europe spoke with many, different voices.

"Sometimes we spend so much time agreeing with one another that when finally the EU comes to the international negotiations we are almost unable to negotiate," she complained.

"Here we must improve, in order to give Europe a stronger voice."

EU nations had agreed prior to the December talks to cut carbon dioxide emissions by 20 percent in 2020 from 1990 levels, with a promise to go further if the rest of the developed world did likewise.

However the climate change conference held in the Danish capital ended with a non-binding agreement which the European Union has blasted as a Sino-US stitch-up which will do little to curtail global warming.

Leaders of some two dozen countries put together a "Copenhagen Accord" that strived to save the gruelling 12-day UN marathon from collapse.

The deal set the aim of limiting warming to two degrees Celsius (3.6 degrees Fahrenheit) over pre-industrial levels, but did not set binding targets to reduce the emissions of gases that scientists say are heating up the world's atmosphere to dangerous levels.

The European parliament is quizzing, this week and next, all 26 nominees for portfolios in EU Commission chief Jose Manuel Barroso's new team.

While the MEPs cannot veto an individual commissioner-designate they can oppose the team as a whole.

From the reaction in the chamber on Friday there appeared to be no major misgivings over the experienced Danish candidate.

Finnish euro MP Satu Hassi said Hedegaard "had demonstrated the political will to be a strong commissioner," even if she had entered the parliament slightly wounded by her ejection from the chair in Copenhagen.