UN Secretary-General António Guterres delivered a stark warning on the unfolding crisis in Ukraine on Monday, saying that the conflict could quickly spread. His remarks came as the Russian invasion entered its 19th day, with peace talks yet to yield tangible results. “Ukraine is on fire,” Guterres said at the UN’s headquarters in New York. “Further escalation of the war, whether by accident or design threatens all of humanity.” Guterres also addressed fears that the conflict could escalate into a full scale nuclear war. “The prospect of nuclear conflict once unthinkable is now back within the …