Global warming. David MCnew via BBC News
The US envoy on climate change John Kerry has warned that the war in Ukraine must not be used as an excuse to prolong global reliance on coal.
Speaking to the BBC, Mr Kerry criticised a number of large countries for not living up to the promises they made at the COP26 climate summit.
Climate diplomats meet again today in Bonn amid new, energy security worries.
If countries extend their reliance on coal in response to the war, then "we are cooked," Mr Kerry said.
COP26 President Alok Sharma at the conclusion of talks in Glasgow - He recently told MPs that political leaders were distracted from climate issues by war and cost of living crises
The fragile unity shown in Glasgow last November is likely to be tested in Bonn as countries deal with the fallout from Russia's invasion of Ukraine and the cost of living crisis.
Mr Kerry told the BBC that despite these drawbacks, "as a world we are still not moving fast enough," to rein in the emissions of warming gases that are driving up temperatures.
"We can still win this battle," the former senator said, but it will require a "wholesale elevation of effort by countries all around the world".
Mr Kerry's call was echoed by a leading Ukrainian scientist who urged delegates to speed up their transition away from fossil fuels.
Dr Svitana Krakovska said oil and gas were the "enablers of war".
Today's meeting in Bonn, which will last until the end of next week, is much smaller than COP26 and is mainly a technical negotiation.
It occurs halfway between the big conferences in Glasgow and COP27, to be held in Egypt.
The talks will be carried out by civil servants with limited political input and will review progress on a host of issues agreed in the Glasgow Climate Pact. - BBC News