UN Secretary-General Ban Ki-moon was in Washington D.C. on Tuesday to discuss the issue of climate change with U.S. officials and Congressional leaders, just a few weeks before the UN conference on climate change to be held in Copehagen in December.

"The secretary-general is in Washington, D.C., where this morning he met with White House officials dealing with climate change," Farhan Haq, Ban's associate spokesman, told a daily news briefing here.

"In the afternoon, he will meet with Congressional leaders to talk about the status of international climate change negotiations, " Haq said.

On Monday, Ban voiced confidence for an agreement next month on fighting global warming even as key issues remain unresolved, a day before he travels to Washington D.C. to discuss with senior officials and congressional leaders what world governments expect in terms of the U.S. role.

"The secretary-general is confident that governments will reach agreement in Copenhagen on the fundamental issues that will form the substance of a legally binding international agreement which is the end goal for guiding action on climate change," the director of the UN secretary-general's Climate Change Support Team, Janos Pasztor, told a news conference at the UN Headquarters in New York on the upcoming summit in the Danish capital.

Although in all likelihood it will not be possible to complete all the work needed for a legally binding agreement at Copenhagen, he said, the meeting should make clear what needs to be done in the three core fundamental issues that remain unresolved -- ambitious mitigation targets in the developed countries, how to consider mitigation actions in developing countries, and financing.

World governments are seeking to agree to a successor to the Kyoto Protocol, the 1997 treaty that committed 37 industrialized States to cutting emissions by an average of 5 per cent against 1990 levels over the period from 2008 to 2012.