A United Nations report on the cyclone that struck Tonga earlier this week says almost all houses in the affected areas of Ha'apai have been damaged.
The Coordination of the Humanitarian Affairs head of office, Sune Gudnitz, says the damage to homes is putting a huge strain on those trying to find shelter.
"The report confirms that there has been extensive damage to housing in the affected areas. We're talking an incredible, nearly 100 percent of the houses in the affected areas are damaged, ranging from severe destruction to light damage, but that of course puts a lot of stress on having to find temporary shelter for people for either the short or medium term."
Sune Gudnitz says water sanitation is an issue for those in temporary housing, and food shortages could also become an issue as crops have been damaged by high winds and salt water.
The report also says 13 of the 17 primary and secondary schools affected in Ha'apai have major damage.
Mr Gudnitz says the UN is on standby to support if the Tongan government formally requests international assistance.
