Bangladesh needs $5bn (£3bn) over the next five years to adapt to current climate changes, and the cost is rising each year, according to a lead negotiator for developing countries in the UN climate talks, which resume in Bonn on Monday, reports The Guardian.
It, and other developing countries, may have been promised $30bn as "fast-start finance" before $100bn a year is theoretically mobilised for developing countries in 2020, the UK-based English daily said.
However, the global recession and reluctance by rich countries to match their pledges with money have meant that most of them receive far less than they expected and has led to a loss of trust in the talks.
"So far Bangladesh has received $200m from the fast-start finance, half of which has come from Britain. We had hoped for much more," said Quamrul Choudhury, who is also Bangladesh's climate envoy to the UN.
"Britain, like us, has not been immune to extreme floods and storms," he said. "You have built defences costing billions of pounds. If we could only build the 700km of coastal defences that we need, it would protect at least 50 million people. It would cost us not much more than $15bn. Our costs are much lower than yours."
The injustice of the poorest countries having to spend heavily to adapt to climate change, which they historically barely contributed towards, is a deep wound in the long-running talks, the next stage of which will finish in Peru with a head-of-state-level meeting with the UN secretary general Ban Ki-moon in September. It has led to a breakdown of trust between countries.
But Choudhury is hopeful that countries will negotiate a legally binding global treaty in Paris next year.
"I am optimistic. China is in a positive mood. The UK, France, Germany, Denmark and Sweden are pushing the EU to raise their ambition. Obama is more positive; I think he will take a leadership role. There is much more awareness now in the talks."
There have been other changes over the years, he says. "Everyone thought in 2008-09 that it would be expensive to reduce emissions. Now we know for certain it doesn't cost much. It's not a herculean task. Countries like the UK know it is possible to go for a 65% cut without losing jobs or hurting growth.
"We know now that [cutting emissions] can create jobs. But to get an agreement means rich countries, especially, must try to rebuild confidence and that means committing money and being prepared to compromise and make sacrifices. The more rich countries give now, the more likely the least developed countries are likely to sign up in Paris."
But he warns that the cost of adaptation is high – and mounting.
"The $100bn a year will not be enough. On top of that we will want a legal mechanism to compensate for 'loss and damage', [compensation for extreme climate change events]. There should definitely be some space in the [final] treaty for that," Choudhury said.
The shame, he says, is that delays are costing countries dear. "Five years will have been lost following the diplomatic debacle in Copenhagen, when developing countries refused to be railroaded into an unsatisfactory agreement.
"If we had succeeded then, we could be implementing a treaty now. Instead we have moved the target to beyond 2020 at the cost of the teeming millions in the least developed countries."