Prime Minister Patrick Manning has told a United Nations Conference on Climate Change that failure to reach an agreement could result in no efforts being made in the future to reduce emissions at levels that can halt the slide towards climate crisis.

"There are many proposals before us on mitigation measures and fast-track financing, among other critical elements for an agreement. Yet, we see a breakdown occurring that threatens to derail the focus on achieving agreement now," Manning told the conference being attended by leaders from more than 120 countries.

"As leaders, we have the capability to leave here with an agreement. We did it in Port of Spain, we can do it in Copenhagen," Manning said, making reference to the Commonwealth Heads of Government Meeting held in his country last month.

He told the summit here that the urgency for a decision is dictated by the plight of the most vulnerable nations.

"What we can do at this point requires an understanding of the circumstances in which major emitters from the developed and some emerging countries find themselves," he said.