Three radical Latin American leaders may make the difference between agreement and failure at the UN climate conference in Cancun, Mexico, which reaches its climax this week.
Hugo Chavez of Venezuela, Evo Morales of Bolivia, and Daniel Ortega of Nicaragua – socialist firebrands all – are planning to attend the "high-level" segment of the Cancun meeting which begins tomorrow – and they each have a specific, potentially deal-breaking demand: that the Kyoto Protocol be renewed. This is because it obliges rich industrialised countries to bind themselves to cut their emissions of greenhouses gases, without a similar commitment by the developing nations.
Their delegates at the conference have already made clear there will be no deal without renewal. Yet last week three major industrialised countries – Japan, Russia and Canada – declared in Cancun they would refuse to renew their initial Kyoto commitments, which run out in 2012.
The rich and poor countries seem so far apart that at the weekend the EU's lead negotiator, Artur Runge-Metzger, said it was "like a sword of Damocles hanging over the conference".
Many negotiators fear that the position can be only further polarised by the arrivals of presidents Chavez, Morales and Ortega, whose nations are collectively known as the Alba countries, because of radical economic grouping they have formed in recent years – the "Alianza Bolivariana para los Pueblos de Nuestra América".
All three are expected later this week at Cancun, along with another Alba member, President Rafael Correa of Ecuador – regarded as more liberal than far-left – although Mr Chavez and Mr Morales in particular can be unpredictable in their behaviour and could yet drop out.
The concern is that they may prevent a compromise deal by treating the conference as an opportunity for radical grandstanding, which Mr Chavez and Mr Morales both did at last year's failed climate conference in Copenhagen – fiercely attacking the final, patched-up agreement, the Copenhagen Accord, for having been negotiated behind closed doors between US President Barack Obama and a small group of other countries.
"Their arrival will definitely affect the dynamic of the conference," a senior diplomatic source at Cancun said last night. "A lot will depend on how it is managed, particularly by the Mexican hosts. And it will also depend on how much progress has been made on the difficult issues by the time they arrive. There is a lot for them to gain by there being a deal, a lot for their populations and economies, so we will have to see how they want to play that with their domestic audiences."
Top of the list of potential gains for developing nations is access to the colossal sum of climate finance – $100bn (£63bn) annually by 2020 – which the rich countries promised the poor countries at Copenhagen. A central part of the Cancun negotiations is the setting up of a new Green Fund to distribute this money, which would be a mixture of public and private finance, although a UN report two months ago said that raising it would be "challenging".
Also on the table is a new forest treaty, which would allow a monetary value to be placed on forests in developed countries which are not cut down (and so do not release carbon emissions to the atmosphere). This too is a potential source of billions for poor nations.
Although negotiations on both of these are advanced, the US has made clear it will block an agreement that does not deal with all CO2 emissions from developing counties, not least because China is the world's biggest carbon emitter. But if the Kyoto problem cannot be solved, a deal is impossible.
"If the extreme positions persist, it will be very difficult to get an agreement at the end of the week," the diplomatic source said. "But we think there will be some movement."