PARIS (AFP) - The UN's pointman on climate change pleaded for calm on Wednesday after angry spats erupted over the outcome of the much-trumpeted world climate summit in Copenhagen.

Yvo de Boer, executive secretary of the UN Framework Convention on Climate Change (UNFCCC), warned 'all this finger-pointing and recrimination' could cloud negotiations next year for sealing a post-2012 pact on tackling global warming.

'We need to work together constructively, whereas countries are in the media blaming each other for what happened, the same countries that are going to have to be back at the negotiating table next year with an open willingness to work together,' he told AFP in a phone interview from London.

'It's bad for the atmosphere, it's bad for the relationship among people that ultimately have a common goal to move this forward.'

De Boer did not name names but chose to give the interview after Britain and China swapped verbal blows as to who was to blame for the Copenhagen outcome, while Brazil took aim at the United States.

Sweden, current president of the European Union, said the summit was a 'disaster' and declared both China and the United States, the world's number one and two polluters, responsible for the disappointing result.

In frenzied backroom haggling on Friday, leaders of some two dozen countries put together a 'Copenhagen Accord' that strived to save the gruelling 12-day UN marathon from collapse.

It was then put to a full meeting of the 194-nation UNFCCC, where it ran into a firestorm early Saturday from a group of Latin American countries and from the spokesman for the G77 group gathering 130 poor nations.

In the end, the conference chairman gavelled the accord through, saying the meeting 'takes note' of the document - a procedural move that enabled its provisions to become operational.

The deal set the aim of limiting warming to two degrees Celsius (3.6 degrees Fahrenheit), but did not set a year by which carbon emissions should peak, nor did it spell out the aim for 2020, the important mid-term target year.

The accord, for the first time, did encompass emissions-curbing pledges by rich and poor nations, although none of these promises are binding.

A total of 30 billion dollars was pledged from 2010-2012 to help poor countries in the firing line of climate change, and rich nations sketched a target of providing 100 billion dollars (141 billion Singapore dollars) annually by 2020.

Green activists and campaign groups slammed the deal for falling far below what scientists are claiming is needed to spear the threat from climate change.

Some singled it out as a backroom deal by the big players that usurped the consensus-driven UN approach.

De Boer urged all parties not to inflate or pull down the importance of the Copenhagen Accord.

'We shouldn't pretend it is anything more or anything less than what it is - an agreement, a sense of direction that can help us in further negotiations.'

He acknowledged, though, that what happened in Copenhagen 'was a very extraordinary event.'

'The fact of the matter is a small group of countries put this accord together, there wasn't enough time to get buy-in from the larger meeting and have it adopted in any kind of formal sense, and that's the reality.'

The lesson from Copenhagen, said De Boer, was that it might be useful for a principal group of countries to propose a deal, but time was needed to have it debated and endorsed in a process 'that is inclusive, representative and transparent.'

He expected the UNFCCC's bureau - a group of top officials dealing with operational matters - to meet early next year to see whether more meetings would be needed in 2010.

At present, the programme is to a high-level meeting in Bonn in mid-year, followed by talks in Mexico City in December 2010 where the hugely complex pact would be sealed.