With just two weeks until the start in Mexico of a major global conference on climate change, the top United Nations official on the issue has emphasized the need for compromise in international efforts to reach a solution to the climate challenge.

"Cancun will be a success, if parties compromise," said the Executive Secretary of the UN Framework Convention on Climate Change (UNFCCC), Christiana Figueres, at a press briefing in Bonn, Germany, today. "They have to balance their expectations so that every one can carry home a positive achievement while allowing others to do the same – that's how multilateral agreements are made elsewhere and it is how it has to happen in climate, too."

The upcoming conference of parties to the UNFCCC – known as the UN Climate Change Conference – takes place in Cancun between 29 November and 10 December. The UNFCCC is an international treaty which considers what can be done to reduce global warming and to cope with whatever temperature increases are inevitable. Some countries have approved an addition to the treaty, the Kyoto Protocol, which has more powerful and legally binding measures.

Figueres acknowledged that there will still be "political gaps" which need bridging among countries attending the conference. These centre on how to move forward with emission reductions, deciding what to do about the Kyoto Protocol and how to anchor the many national targets and actions governments have put forward, in particular the targets of industrialized countries.

While expectations for agreements on how best to tackle climate change at the conference are realistic, Ms. Figueres noted, "there's still a lot at stake if the world is going to stay below a two degree temperature rise."

In response to a question, Ms. Figueres said that the conference needs to conclude with a balanced set of decisions, including on the issues of adaptation, forestry and technological cooperation. However, she said, in order to be a balanced package, any "agreement must also address the mitigation efforts by both industrialized countries as well as those developing countries that have already put mitigation intents on the table," as well as provide some resolution about what the continuation of the Kyoto Protocol is going to be and the next steps to be taken by countries in relation to long-term financing of climate change measures.

The climate change chief said that any agreement on tackling climate change in Cancun is not going solve the whole problem. "But it can set a new pace for negotiations, where governments lock in better agreements every year, never ruling out new possibilities or ignoring existing needs for the future," she said, adding that if climate change is humanity's biggest long-term challenge, it is also its greatest opportunity.

"It is the sustained and increasingly ambitious long-term response to climate change that will allow a successful adjustment to the other great political, economic and social changes which all countries face," Ms. Figueres said.