* Developed nations to talk more about 2020 cuts
* African nations win promise of more meetings
* Africa group says will repeat boycott if no progress Wed.
BARCELONA, Spain, Nov 3 (Reuters) - African nations called off a day-long boycott at U.N. climate talks on Tuesday after winning promises that rich nations would make more efforts to deepen 2020 cuts in greenhouse gas emissions.
But the group threatened to repeat the boycott if there was no progress in discussions on Wednesday.
"We were able to arrive at a solution," John Ashe, an official of Antigua and Barbuda who chairs negotiations among parties to the U.N.'s existing Kyoto Protocol, told delegates at the 175-nation meeting in Barcelona.
"Failure ... in tomorrow's discussions will give us no option but a suspension," of the talks again, said Pa Ousman Jarju from the delegation of Gambia, one of leading countries which organised the Africa boycott.
The African countries boycotted some of the talks in protest at what they called inadequate promises by developed nations for cutting greenhouse gas emissions by 2020 as part of a U.N. deal due to be agreed in Copenhagen next month.
African delegates said their nations are most exposed to droughts, floods, wildfires, desertification, disease and rising sea levels projected by U.N. studies as a result of global warming caused mainly by burning fossil fuels.
Under Tuesday's compromise, six of 10 remaining Kyoto sessions at the Nov. 2-6 negotiations in Barcelona would focus on cuts in greenhouse gas emissions by industrialised nations -- one of biggest stumbling blocks to a Copenhagen deal.
African delegates said the change of schedule had to be matched by a real willingness to cut emissions.
African nations say developed states should cut emissions by at least 40 percent below 1990 levels by 2020 -- far deeper than cuts on offer so far ranging from 11 to 15 percent. Barcelona is the final U.N. session before Copenhagen.
Earlier, Kemal Djemouai, chair of the African group, explained the protest, saying: "People in Africa are suffering now, people are dying now, when the developed countries are not willing to express...ambitious reductions."
The protest cancelled all meetings on Tuesday about an extension of the Kyoto Protocol, which binds all industrialised nations except the United States to cut emissions by 2012.
Alf Wills, the head of the South African delegation, said Tuesday's compromise would also mean a more serious discussion about how cuts would be achieved -- for instance by offsets or investing in forestry.
Developing countries have reiterated charges that rich nations were trying to "kill Kyoto" by merging it into a single pact in Copenhagen. They want rich nations' pledges under Kyoto kept separate from their own actions.
"It is becoming official that they do want to walk away and discard the Kyoto Protocol...We find that fundamentally objectionable," said Lumumba Sanislaus Di-Aping, of Sudan who chairs the Group of 77 and China.
Spanish Environment Minister Elena Espinosa confirmed the European Union favoured merging talks on Kyoto with a broader deal, rather than extend the Protocol.
"We have a preference for a single legally binding agreement," she told Reuters.
Editing by Matthew Jones
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