Labour MP Ed Miliband has called on Britain to acknowledge its "historical responsibility" and send cash to countries affected by climate change.
The former leader of the party proclaimed it is "morally right" to help countries such as Pakistan and the Maldives who have been ravaged by flood damage.
But his comments have been met with widespread criticism from Conservative MPs.
Craig Mackinlay, founder of the Net Zero Scrutiny Group told the Daily Mail: "Labour have let the cat out of the bag here as to their plans to give untold billions to countries on the premise that there is climate damage being done.
Ed Miliband has called on Britain to acknowledge its 'historical responsibility'.
Peter Byrne
"How on earth we could be held responsible for our past, which actually gave more technological advances to the world than any other country, I find somewhat laughable."
The row comes as Rishi Sunak travelled to Egypt for the Cop27 conference, where he will meet with other world leaders to discuss the global strategy on facing up to climate change.
Britain is set to face demands for "environmental reparations" at the conference.
Rishi Sunak is attending the Cop27 conference despite previously stating that he would not do so.
Victoria Jones
China were rebuffed in their demands for a financial package at last year's Cop26 conference in Glasgow, the UK Government are likely to deny any similar request this year having pledged to stop sending aid to the country.
Mr Miliband, Labour's climate spokesperson, was questioned over the weekend as to how the Government should assist developing nations in their battle against climate change.
He told the BBC: "I don’t see it as about reparation … this is about the issue of so-called loss and damage, this is the fact that poorer countries are facing massive effects of climate change.
"The terminology matters because lots of people are allergic to the term reparations."
Pressed on whether Labour would spend the money, he said: "Absolutely it’s about supporting poorer countries, completely right, and let me just say it’s morally right, but it’s also in our self-interest too.
"Because if we don’t act and if we don’t help countries around the world, we’re going to end up with the problems that countries face in terms of refugees for example coming back on to us. This is about countries like the Maldives, like Pakistan and others."
A Labour spokesman told the Daily Mail that the party's former leader had been discussing overseas aid spending, as Labour do not have an official stance on reparations.
He said: "Like the UK Government, we support the addition of loss and damage to the agenda for Cop27 for world leaders to discuss.
"Labour would return UK development spending to 0.7 per cent of GDP to ensure that we can strengthen our energy security here at home by bolstering energy security abroad."