Updated

Diplomats say Nikki Haley, in her first week as U.S. ambassador, is making a top priority of reform in the United Nations' far-flung peacekeeping operations that cost nearly $8 billion annually.

Haley said in her Senate confirmation hearing that she wants to look at all 16 missions to see which are maintaining peace and which aren't. She called the mission in war-ravaged South Sudan, the world's newest nation, "terrible" and said that government isn't cooperating with the U.N. force.

Two diplomats speaking on condition of anonymity because conversations were private said that in discussions this week Haley put a mission-by-mission review of peacekeeping operations as a main priority.

The United States currently pays 28.57 percent of the U.N. peacekeeping budget, nearly triple the second-largest contributor China.