Most expensive peacekeeping operation

The most expensive United Nations peacekeeping mission to date is UNPROFOR (United Nations Protection Force), which cost $4.6 billion (£2.96 billion) from 12 January 1992 to 31 March 1996 and included all the missions deployed in the former Yugoslavia during this period, and those after the formal end to the Mission in March 1995. This equates to a shade under $3 million (£1.93 million) per day. 

In March 1995 UNPROFOR was restructured into three inter-linked peacekeeping operations: UNCRO, UNPREDEP and UNPF-HQ.