World leaders and finance ministers descended on London this week for a landmark climate finance summit, with pledges topping $500 billion to support developing nations in their green energy transition — the largest single commitment in the history of climate diplomacy.

The two-day summit, hosted by the UK at the ExCeL Centre in East London, brought together representatives from 80 countries as well as major private sector institutions including BlackRock, HSBC, and Barclays, who collectively pledged an additional $120 billion in green infrastructure financing.

UN Secretary-General António Guterres called the summit "a turning point in humanity's response to the climate emergency," though he cautioned that pledges alone were insufficient without clear delivery mechanisms and timelines.

A key breakthrough came on the second day when a coalition of G7 nations agreed to a new framework for debt relief tied to climate adaptation spending in the most vulnerable economies. Small island nations and sub-Saharan African countries had long called for such a mechanism.

Climate campaigners outside the venue staged peaceful protests, arguing the pledges still fell short of what science demands to limit warming to 1.5°C. Greta Thunberg, addressing a crowd of several thousand, said: "We need transformation, not promises."

The UK government committed to doubling its international climate finance contribution to £2 billion annually from 2027.