The United Nations Framework Convention on Climate Change (UNFCCC) was ratified in 1994, with 198 countries signing up to act on global warming.

Over 20 years later, at COP21 in Paris, the parties agreed a landmark treaty covering climate change mitigation, adaptation and finance, with the key commitment to limit global warming to well below 2 C on pre-industrial levels.

COP27, held in Sharm el-Sheikh, Egypt, took place amid geopolitical instability and a crisis around energy security and prices. The outcomes of the conference were mixed. Only 35 nations came to the event with new or updated pledges to cut emissions, known as nationally determined contributions, or NDCs, and world leaders did not make further progress on agreeing a phase out of all fossil fuels. But negotiators achieved a landmark agreement to establish a fund on loss and damage.

COP28 in the UAE will mark the conclusion of the global stocktake, a two-year process under the Paris Agreement that aims to assess collective progress and identify a roadmap of actions to accelerate and supercharge efforts to tackle climate change. Delegates will also tackle issues including how to make progress on the charged issue of a fossil fuels phase out; the setting of ambitious renewable energy targets and financing goals; and international carbon trading and accounting.

Since the beginning of the year, government ministers, company officials and representatives of multilateral organizations have been preparing for COP28 through high-profile events like the G7 and G20 meetings and regional climate summits. The timeline below shows the major events that laid the groundwork for the event.