Forecasters says winds could reach 200 kilometres an hour as an intensifying Cyclone Rene bears down on Tonga.
Rene, a category 3 cyclone on Sunday evening, had passed Samoa where it brought high winds and lashing rain.
The Fiji Meteorological Service says the cyclone will probably reach category 4 by the time it hits Tonga's capital, Nuku'alofa, mid-afternoon on Monday.
Radio New Zealand International reports it's feared the storm could cause severe damage in Tonga, where many survivors of last year's deadly tsunami have only tents for shelter.
In Niue, police were on Sunday evening advising people to take precautions as the cyclone passed to the northwest of the island on its way to Tonga.
Cyclone spares Samoa
Samoa and American Samoa were spared the worst of Tropical Cyclone Rene.
The south east of Samoa's island of Upolu, which bore the brunt of the damage from last September's tsunamis disaster, was the most-affected part of the country as Cyclone Rene passed nearby.
Goretti Wulf of the Red Cross in Samoa says people are relieved to not have experienced a natural disaster of the magnitude of the tsunami and the only damage was a few fallen trees.
However, in American Samoa, Cyclone Rene left one dead, uprooted trees and caused landslides and flooding as it swept past the territory.