Bonn, June 6 : US Special Presidential Envoy for Climate John Kerry has warned that the war in Ukraine must not be used as an excuse to prolong global reliance on coal. Kerry, who is currently in Bonn for talks with climate diplomats, 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," he said, but it will require a "wholesale elevation of effort by countries all around the world". Speaking to the BBC, Kerry criticised a number of large countries for not living up to the promises they made at the COP26 climate summit. If countries extend their reliance on coal in response to the war, then "we are cooked", he said. Kerry's call was echoed by a leading Ukrainian scientist who urged delegates to speed up their transition away from fossil fuels. Svitana Krakovska said oil and gas were the "enablers of war". Monday'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. /IANS