United Nations Secretary General Ban Ki-moon called Saturday for a legally binding treaty on climate change as soon as possible in 2010.

He said the negotiation process at the climate conference here was by far the most complicated he had known. That was because of the many countries attending, all with different positions and situations and different domestic difficulties, he explained.

He said the conference had agreed to "take note of the Copenhagen Accord," which was expected by many to be "accepted." His assistant later explained that the words "take note of" and "accept" were nearly equal in legal terms.

The Copenhagen climate change conference, which was scheduled to end on Dec. 18, has been postponed to Dec. 19 because of the disagreement of several developing countries, including Bolivia, Cuba, Sudan and Venezuela. These countries said they could not accept the Copenhagen Accord draft because it lacked ambitious targets for reducing carbon emissions.

After managing to persuade the parties to "take note of the Copenhagen Accord," Ban urged them to translate it into a legally binding treaty as soon as possible in 2010.

He added that any necessary measures would be taken to facilitate a treaty. Ban's efforts to seal a deal on Friday resulted in him not eating until Saturday morning and sleeping only two hours in the past two days.

He also said a Copenhagen green climate fund would be established next year and would take necessary measures to fund developing countries on mitigation actions.