UN Secretary General Ban Ki-moon admitted the UN climate summit in Copenhagen fell short of its goals but called it an important step toward a global agreement needed to combat climate change. (Heribert Proepper/Associated Press)

United Nations Secretary General Ban Ki-moon on Monday defended the results of the Copenhagen climate change talks as a significant step toward a binding agreement on reducing greenhouse gas emissions.

He made the comments to reporters on Monday in response to criticism from world leaders that the process was flawed.

Coming up with an accord member states could agree on was "quite difficult," Ban said, but he said he was encouraged by the results.

"It is not perfect at this time, but it was a very important and very significant step forward," he said.

The three-page Copenhagen accord, put forward by a U.S.-led group of five nations — including China, India, Brazil and South Africa — recognizes that an increase in global temperature should be kept to two degrees Celsius — the threshold that UN scientists say is needed to avert serious climate change.

But the accord is not legally binding and has no long-term global targets for emissions cuts.

It also promises to deliver $30 billion US in aid over the next three years to help developing nations reduce emissions.

Although the agreement was not formally approved, the conference president said that delegates at a late-night plenary session agreed to "take note" of the document, or recognize that it exists.

Ban urged all countries to sign on to the accord and work toward making it a binding agreement next year.

Finger-pointing after summit

Though Ban was optimistic, the Copenhagen talks revealed deep divisions in the international community.

Several countries, including Bolivia, Cuba, Nicaragua, Venezuela and Sudan, called the accord unacceptable and said it had not been reached through a proper process.

British Prime Minister Gordon Brown said Monday that some countries held the summit under ransom with their demands. Although Brown did not name names, his representative at the talks, Ed Miliband, said China led a group of countries that "hijacked" the negotiations and prevented the establishment of emission-reduction targets.

Brazilian President Luiz Inacio Lula da Silva also took a shot at the United States on Monday, saying its stance at one point prompted many European nations and Japan to reconsider implementing the Kyoto Protocol.

The UN had hoped the Copenhagen talks could come up with an agreement that could replace Kyoto, which is set to expire in 2012.

Danish Prime Minister Lars Loekke Rasmussen, who hosted the summit, complained that lower-level negotiators failed to make enough headway in nearly two weeks of talks, leaving much of the work to be done by leaders at the end of the summit.

With files from the Associated Press