By EDITH M. LEDERER
UNITED NATIONS (AP) — The U.N. special envoy for Sudan who was declared unwelcome by the country’s military government in June has resigned. He is warning that the conflict between Sudan’s two military leaders “could be morphing into a full-scale civil war.” Volker Perthes had continued to work outside Sudan. He told the U.N. Security Council on Wednesday that the fighting in Sudan shows no sign of abating. At least 5,000 people have been killed but he warned the figure was conservative and the true number is likely much higher. Perthes was a key mediator after the conflict began, but the government claimed he was biased and informed the United Nations that he was declared a persona non grata.