The European Union warned on Saturday that a U.N. summit in Madrid must send a strong signal that countries are ready to do more to cut emissions, as fears grew that international efforts to fight climate change were slipping into reverse. The two-week round of annual climate negotiations had been due to conclude on Friday, but dragged on into the weekend as delegates failed to resolve multiple disputes over implementing a climate accord forged in Paris four years ago. Krista Mikkonen, Finland’s environment minister, speaking on behalf of the EU, told the latest session at the talks that it would be “impossible to leave” without agreeing a “strong message” on the need to redouble pledges […]