26 Mar 2013 Security Council extends mandate of Peacebuilding Office in Sierra Leone for final time, with operation to fully draw down by 31 March 2014 26 March 2013 - Security Council extends mandate of Peacebuilding Office in Sierra Leone for final time, with operation to fully draw down by 31 March 2014. The UN engages citizens around the world to take part in shaping the future global development agenda. Secretary-General celebrates peacebuilding ‘triumph’ in Sierra Leone at closing ceremony of United Nations Integrated Office