Many industrialised nations are shelving ambitions for the deepest cuts in greenhouse gas emissions by 2020 as economic slowdown overshadows the fight against climate change.
About 190 countries meet for UN climate talks in Poznan, Poland, this week with scant mention of a deal in Vienna last year by almost all rich nations to consider cuts in emissions of 25-40 per cent below 1990 levels by 2020.
"That target is perhaps something that's on the back-burner for the time being," said Rajendra Pachauri, head of the UN Climate Panel that said last year that industrialised nations needed to make such cuts to avoid the worst of warming.
Struggling with the worst financial crisis since the 1930s, everyone from US President-elect Barack Obama to European leaders are focusing more on stimulus packages that should help a shift from fossil fuels by creating 'green' jobs.
Pachauri said world leaders might find it easier to discuss ambitious cuts in a few months, "after the dust settles" from the financial crisis. Poznan will review progress towards a new climate treaty to be agreed by the end of 2009 in Copenhagen.
But he also told Reuters: "If we want to limit temperature increase to 2˚C (3.6˚F), or thereabouts, then clearly (25-40) is the target we should be watching."
Two Celsius is seen by the EU, some other nations and many environmentalists as a threshold for 'dangerous' climate change - disrupting water supplies, farming and causing more coastal floods from rising sea levels.
"Only the EU and Norway" have discussed cuts within the 25-40 per cent band, said Harald Dovland, a senior Norwegian official who chairs a UN climate committee in Poznan looking at future pledges by industrialised nations. The idea of 25-40 per cent cuts was always a stretch. But the Vienna agreement is likely to haunt many - deep cuts by rich nations are often brandished by developing nations such as China and India as a pre-condition for the poor to start curbing their own rising emissions.
And the EU's target only reaches Pachauri's band because the 27-nation bloc has offered to cut emissions unilaterally by 20 per cent below 1990 levels and by 30 per cent by 2020 if other nations follow suit.
The 30 per cent path, analysts say, looks ever more unlikely.
Obama's United States, Japan and Canada plan cuts that would return their emissions to around 1990 levels by 2020. Australia will announce a 2020 goal before Poznan. Russian emissions are far below 1990 levels after the collapse of Soviet-era industry.
The EU, which sees itself as a climate leader, is struggling to carry through its unilateral goal and is handing concessions to heavy industry before a December 11-12 summit meant to seal the pact over objections from Italy and Poland.
Dovland said the jury was still out on the final impact of the financial crisis.
"I hear both versions. Some say 'we cannot', others say 'this is an opportunity to change to a low carbon society'," he said.