Amid tears, boos and sallow faces signalling sleepless nights,a UN climate conference adopted a plan to negotiate a new global warming pact by 2009when the United States suddenly reversed its opposition Saturday to changes proposed by developing nations.

Theagreement came after marathon, emotionalovernight negotiations, which first settled a battle between Europe and the U.S. over whether the document should mention specifictargets forgreenhouse-gas cutsby rich countries.

The new deal does not commit countries to specific actions against global warming. It simply sets an agenda for negotiators to find ways to reduce pollution and help poor countries adapt to environmental changes by speeding up the transfer of technology and financial assistance.

Despite an aggressive EU-led campaign to include specific emissions reduction targets for industrial nations — by 25 to 40 percent below 1990 levels by 2020 — the final road map has none.

Earlier, UN Secretary-General Ban Ki-moon, who had rushed back to the conferencein the wee hours ofSaturdaymorning to implore delegates to come to a consensus,said he was disappointed by the level of progress at the Balitalks and urged delegates to quickly approve a compromise plan to launch negotiations for a new global warming pact.

A last-minute dispute between developing countries and theUN had blocked progress at the two-week conference, despite a compromise that resolved a dispute between the United States and Europe.

Ban, who addressed the conference in an attempt to smooth over the differences, said the proposed plan was "good and strong" and should be adopted.

"Frankly, I'm disappointed about the lack of progress," Ban told delegates.

The conferencewas marked by a fierce battle between the European Union, which had argued for explicit goals for reductions in greenhouse gas emissions by 2020, and the U.S., which at one point attracted boos from delegates and whichheldthat targets should be determined by two years of upcoming talks.

The EU said Saturday it backed a compromise proposal. But in an unusually harsh statement, China accused the UN of calling on delegates to vote on the document even though developing nations were still negotiating for changes. India also objected to a part of the text.

Talks on the document, which lays out the agenda for further climate talks that are to lead to a global warming pact to take effect at the end of 2012, had run through the night. Delegates were debating how far future negotiations should go in trying to cut emissions of greenhouse gases that contribute to global warming.

At one point, an emotional and sallow-lookingYvo de Boer, the UN's climate chief, who hadn't slept in two days,broke downin tears at the deadlock in negotiations. Delegates applauded him and he regained composure.

The negotiating agenda set at Bali, and the results of two years of negotiations to follow, will help determine for decades to come how well the world can hold down its rising temperatures.

Reaction to Canada's performance at the conference was sharp. Quebec Environment Minister Line Beauchamp, who attended the talks, said she was disappointed the country didn't do more.

"Did Canada play the leadership role we were expecting? I think the answer is no, that it was disappointing."

Sparring for days

Delegates had sparred for days over the wording of the conference's main decision document.

Trying to break the deadlock, conference president and Indonesian Environment Minister Rachmat Witoelar proposed revised language dropping explicit mention of numbers while substituting a reference to a UN scientific report suggesting the 25-40 per cent range of cuts.

Witoelar's proposal provided a basis for a long-expected compromise, producing a relatively vague mandate for the two years of negotiations. As worded, his draft "Bali Roadmap" would not guarantee any level of binding commitment by any nation.

On developing countries, including such big emitters as China and India, the draft would instruct negotiators to consider incentives and other means to encourage poorer nations to voluntarily curb growth in their emissions.

UN climate chief de Boer said worldwide public opinion was forcing the more than 180 national delegations to find a way to agree.

"I don't think any politician can afford to walk away from here," he told reporters. Asked if that included the U.S., he responded, "Perhaps most of all the United States."