A group of former leaders and climate experts said the annual U.N. COP climate talks were no longer fit for purpose and needed to be reformed, publishing a critical open letter mid-way through what has so far been a fractious summit.

The next major United Nations meeting on climate change, known as COP29, is about to get underway in Baku, Azerbaijan. These annual meetings are the key international summits as the world attempts to address the unfolding climate crisis.

A group of conflict-affected countries is pushing at COP29 to double financial aid to more than $20 billion a year to combat the natural disaster and security crises facing their populations, a letter seen by Reuters showed.

Developing countries need at least $1 trillion per year by the end of the decade to cope with climate change, economists told U.N. talks in Baku, where early efforts to reach a finance deal risk being overshadowed by diplomatic rows.

"You owe us!" screamed a protest banner at the COP29 summit in Azerbaijan, where negotiations over how much rich nations most responsible for climate change should pay poorer ones are