The UN Secretary-General Ban Ki-Moon called for clarity of the legally binding Kyoto climate agreement in Copenhagen Tuesday.

UN Secretary-General Ban Ki-Moon addresses journalists at a press conference with Danish Prime Minister Helle Thorning-Schmidt in Copenhagen, Denmark, Oct. 11, 2011.

"I hope the member states will have serious discussions in Durban. In Durban, there must be discussions on the clarity of the future of the Kyoto Protocol," Ban Ki-Moon said, referring to the up-coming UN Climate Change Conference in South Africa's Durban from Nov. 28 to Dec. 9.

Ban was addressing journalists at a press conference with Danish Prime Minister Helle Thorning-Schmidt in Copenhagen while on a four-day working visit to Norway, Denmark and Sweden.

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The Kyoto Protocol is an international agreement that sets binding targets for 37 industrialized countries and the European community, committing them to reduce their greenhouse gas emissions by an average of five percent against 1990 levels in the period 2008-2012.

Discussions on the Kyoto Protocol have assumed great urgency as the treaty runs out end 2012, after which it will have to be replaced by a new framework.

"What is important at this time is that the(UN) member states should build up on what has been agreed in Cancun last year. Cancun was able to build on what had been discussed in the Copenhagen conference," Ban remarked.

Copenhagen, the Danish capital, and Cancun, in Mexico, hosted the 15th and 16th UN Climate Change conferences, respectively.

"We have made reasonably good progress in several areas like adaptation, capacity building, climate change financing, deforestation and technological transfer," he added.

His trip here also included a meeting with Denmark's Queen Margrethe II, bilateral talks with Danish prime minister Helle Thorning-Schmidt, and a visit to the UN City buildings in eastern Copenhagen, which are scheduled to open 2012-2013.

Thorning-Schmidt and Ban discussed how to promote green growth and sustainable development, as well as Denmark's upcoming presidency of the European Union, starting Jan. 1, 2012, which promises to make green growth a high priority.

"Denmark's entire electricity and heat supply must come from sustainable energy in 2035. It's a very high goal and we plan to achieve it," Thorning-Schmidt added.

The UN chief now heads to Sweden where he will meet Prime Minister Fredrik Reinfeldt and other top officials, before returning to New York, the UN headquarter on Wednesday.

Ban previously visited Denmark in December 2009, when it hosted the 15th UN climate conference.