The world's richest countries "must deliver" financial aid to climate-vulnerable nations, COP26 president Alok Sharma has said.
During a two-day visit to Bangladesh, Mr Sharma told Sky News developing nations were frustrated by a failure by G7 nations to meet a financial target of $100bn (£71bn) per year for climate-related issues.
"This has become a matter of trust," Mr Sharma said. "A totemic figure that always comes up in my discussions with developing nations.
"We need to collectively, as developed nations and donor nations, deliver on that."
Mr Sharma's trip to Bangladesh is part of a tour of the region's most climate-vulnerable nations, ahead of the COP26 summit due to be held in Glasgow this November.
He is urging all nations to stick to targets made during the 2015 Paris COP, which saw countries pledge to make carbon emissions cuts in order to limit global temperature rise to under 2C.
Mr Sharma has previously said ending reliance on coal-powered energy production was his "personal priority".
"In the case of Bangladesh, I've raised this issue with ministers here and I've been pleased to hear that they are already looking at reducing the number of new power plants," he said.
"But of course the way to ensure we consign coal to history is to also support countries like Bangladesh to make that clean energy transition."
It is estimated that trillions of dollars - a mix of public and private money - will be needed for renewable energy infrastructure across the globe.
But a new report, released by NGO Care Denmark, says that most G7 countries have still made no fresh commitments on climate finance.
Climate finance is set to be a key topic at this year's COP26.
When questioned on why G7 countries are yet to meet previous financial pledges, Mr Sharma said: "We are working with partners to deliver on [financial commitments] on the road to COP26."
It comes as a poll found almost two-thirds of people back government commitments to provide financial and tech support to poorer countries in a bid to shift to clean energy.
A YouGov survey of 1,750 people for climate think tank E3G found more than half agreed everyone would suffer the consequences of climate change - and that it was in Britain's interests to help poor countries switch to greener resources.
Millions in Bangladesh were forced to flee their homes last year after severe floods triggered by monsoon rains.
The deluge affected almost a third of the country, with many of the 16 rivers in Bangladesh overflowing.
At least 161 people died, according to local media reports.
The country banned fishing in coastal areas for 65 days in May 2019 in a bid to preserve its marine populations.
Every day at 6.30pm, Sky News broadcasts the first daily prime time news show dedicated to climate change.
Hosted by Anna Jones, The Daily Climate Show is following Sky News correspondents as they investigate how global warming is changing our landscape and how we all live our lives.
The show will also highlight solutions to the crisis and show how small changes can make a big difference.