29. Unless all concerned, and especially the Bosnian Serb party, respect the freedom of movement of UNHCR and UNPROFOR, there is little that UNPROFOR can do to ensure more effective implementation of the tasks assigned to it in the humanitarian field. The view expressed by some that the use of force by UNPROFOR, including the application of air power, would make it possible to "fight the convoys through" to the besieged safe areas across the confrontation lines overlooks two important factors: first, the vulnerability to reprisals of dispersed personnel of the United Nations and non-governmental organizations (NGOs) and, second, the fact that the Force has neither the mandate nor the military resources to initiate operations to ensure that no party could block the convoys' progress by any means. Military protection serves primarily to dissuade random or unorganized attacks, it cannot substitute for the consent and cooperation of the parties.

E."No-fly zone"

30. Resolution 781 (1992) declared a ban on all military flights in the airspace of Bosnia and Herzegovina and mandated UNPROFOR to monitor compliance with it and to ensure that the purposes of flights to and from Bosnia and Herzegovina were consistent with Security Council resolutions. Resolution 816 (1993) expanded the ban on air activity and authorized Member States to take "under the authority of the Security Council and subject to close coordination with the Secretary-General and UNPROFOR, all necessary measures" to ensure compliance with it. Both resolutions were adopted under Chapter VII of the Charter. Since 12 April 1993, aircraft of the North Atlantic Treaty Organization (NATO) have, at my request, flown in the airspace of Bosnia and Herzegovina to enforce the no-fly zone.

31. UNPROFOR's role as regards this part of its mandate is confined to ground monitoring at selected airfields in the area, all action related to enforcement is undertaken by NATO. Despite a large number of violations by helicopters carrying personnel ("flying trucks"), the no-fly zone has been

largely successful in discouraging the use of the airspace of Bosnia and Herzegovina for combat purposes. A recent exception, however, involved several sorties flown by the Croatian air force through Bosnian airspace to bomb positions in Sector West in Croatia.

F. Border monitoring

32. In resolutions 787 (1992) and 838 (1993) the Security Council asked me to consider adding to UNPROFOR's mandate the task of deploying monitors on the borders of Bosnia

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