The impact of munitions use in built-up areas will be the focus of a conference of countries in Ireland this week expected to endorse a declaration committing to restrict the use of explosives in such settings.

Explosive weapons used in populated spaces have the gravest consequences, top officials from the United Nations and the International Committee of the Red Cross said in a joint statement.

The use of these weapons in urban areas "claim countless lives and limbs, cause widespread destruction," they said.

Russia's war in Ukraine is the latest example of the devastation wrought by missiles, bombs and other explosive weapons in urban areas.

The UN and ICRC have for years been calling on nations to commit to refrain from using munitions in places where civilians live and congregate.

After three years of consultations, countries will meet in Dublin on Friday to endorse the call.

UN aid chief Martin Griffiths pointed out that explosive weapons in populated areas only add to the despair of civilians who "already bear the greatest brunt in conflict", describing such use as an "immense humanitarian catastrophe".

UNICEF chief Catherine Russell highlighted in particular the impact of such weapons on children.

"To bomb a home, school, hospital -- any place children live, learn, or rely on -- is indefensible," she said.

The new declaration could be an important step in that direction.

The ICRC's new president Mirjana Spoljaric, who will be at Friday's signing ceremony, pointed out that countries would for the first time be "committing to curbing the use of explosive weapons in populated areas".

This, she said, was "a critical acknowledgement of the magnitude of the problem."