Armed conflicts are increasingly fought in population centres, and this urbanization of armed conflict has resulted in devastating and well-documented impacts on civilians. This is often due to the use of weapons systems that are designed for traditional open battlefields.

A leading concern is the use in populated areas of explosive weapons with wide-area impacts. These include weapon systems, munitions and tactics used by States and non-State actors, which can be expected to result in a high proportion of incidental civilian harm if employed in areas where there is a concentration of civilians.

Problematic types of weapons include indirect fire weapons, such as artillery, rockets and mortars, weapons that fire in salvos, such as multi-launch rocket systems, large air-dropped bombs and surface-to-surface ballistic missiles. Such systems variously involve munitions with a large destructive radius, weapons with inaccurate delivery systems or weapon systems that deliver multiple munitions over a wide area.

Many of these weapons are inherently indiscriminate when used in populated areas and therefore result in increased civilian casualties and devastating humanitarian impacts. According to some estimates, more than 90% of those killed and injured in such situations are civilians. Many more are affected by the reverberating effects of such use when social, commercial, infrastructural, cultural, educational, religious, and health-care facilities are shattered. Parties to armed conflict must always give due weight to the reasonably foreseeable effects of using bombs, missiles, mortars, rockets, artillery and other explosive weaponry – certainly also in populated areas. The collection of data on civilian casualties is another important practical step that parties to conflict, the United Nations, humanitarian entities and other interested actors should take to effectively address concerns raised by the use of explosive weapons in populated areas.

Since 2009, the Secretary-General, in his reports to the Security Council on the protection of civilians in armed conflict, has consistently highlighted the indiscriminate and severe humanitarian impact of the use of explosive weapons in populated areas.

The Secretary-General has called for parties to conflict to avoid locating military objectives within or near densely populated areas; to ratify or accede to core international instruments aimed at protecting civilians, including the Arms Trade Treaty and similar regional instruments; and to engage constructively in efforts to avoid the use of explosive weapons with wide-area effects in populated areas and to develop a political declaration that would, inter alia, commit States to develop operational policies based on a presumption against such use..

Reports of the Secretary-General to the Security Council on the protection of civilians in armed conflict

In his Agenda for Disarmament Securing Our Common Future, the Secretary-General placed special emphasis on addressing the use of explosive weapons in populated areas and committed to support States in developing a political declaration as well as limitations, common standards and operational policies in conformity with international humanitarian law.

In September 2019, the Secretary-General and the President of the International Committee of the Red Cross issued a joint appeal calling on parties to armed conflicts to avoid the use of explosive weapons with wide area effects in populated areas, due to the significant likelihood of indiscriminate effects.

Joint Appeal by the UN Secretary-General and the President of the International Committee of the Red Cross on the Use of Explosive Weapons in Cities