The UN's peacekeeping chief Herve Ladsous expressed his frustration with South Sudan's leaders Wednesday, saying President Salva Kiir and his government have denied repeated requests for the UN mission there to use equipment needed to protect civilians.

Ladsous laid out to the UN Security Council the problems that his 12,000 troops, police and civilian personnel in South Sudan have been experiencing because of the government's lack of cooperation, the Voice of America (VOA) website reported.

"I see a country and I can be very candid, that country is South Sudan a country where we felt that we needed to do a better job to protect civilians," he said, adding "We needed attack helicopters request denied. We needed UAVs [unmanned aerial vehicles, or drones] request denied by the president to me, personally, three times last year." Ladsous said the mission's movements have also been restricted. Also troubling, he said, is that the South Sudan government is finding new ways to harass and intimidate mission personnel.

"Juba did declare some of our senior personnel persona non grata," he said. "If you look at the fact that yesterday it was announced that from now on UN personnel who are taking pictures will be considered as spies, well, I think this raises a number of concerns." For over a year, the UN has been sheltering more than 100,000 civilians who have sought protection at hastily set up camps inside UN bases in some of the worst-affected areas.

The civilians are fleeing fighting that ignited after a political rivalry between Kiir and his former vice president, Riek Machar, escalated into open conflict in December 2013. Tens of thousands have died since, and the two men have not heeded international warnings to adhere to a cease-fire deal made in January 2014 and start working toward a transitional government.