London | As Climate Change and Energy Minister Chris Bowen jetted into Azerbaijan to help land the latest COP climate deal this week, the US climate envoy John Podesta was in the Baku airport departures lounge, heading the other way.

Bowen and his ministerial counterparts from almost 200 countries will spend the next few days wrangling bitterly over how much money richer countries should give poorer ones each year to fight climate change – $US1 trillion-plus ($1.6 trillion) is the ask. They’re also locking horns, again, on the wording of a commitment to “transition away” from coal, oil and gas.