Some 12,000 households have been affected by the volcanic eruption and tsunami that hit the islands of Tonga, a United Nations official told China Media Group (CMG) in an interview on Friday.

Currently, 23 UN staff are working in Tonga and have traveled and evaluated almost the entire country after the natural disaster, United Nations Office for the Coordination of Humanitarian Affairs (OCHA) head Anne Colquhoun told CMG.

She said that 31 houses along the coastline are known to have been completely destroyed, 72 houses were severely damaged and dozens more suffered moderate or mild damage.

Colquhoun also noted the international community's respond to relief work in Tonga, adding China has acted the most quickly.