Countries agreed on a deal to inject at least $300 billion annually in humanity's fight against climate change, aimed at helping poor nations cope with the ravages of global warming at tense United Nations climate talks in the city where industry first tapped oil.

The petroleum-laden dust has settled on this year’s United Nations climate summit, COP29, held over the past fortnight in Baku, Azerbaijan. Climate scientists, leaders, lobbyists and delegates are heading for home.

The world approved a bitterly negotiated climate deal on Sunday (Nov 24) but poorer nations most at the mercy of worsening disasters dismissed a US$300 billion a year pledge from wealthy historic polluters as insultingly low.