The New Zealand Red Cross says drinking and cooking water is being rationed in Tuvalu because due to a severe water shortage.
The New Zealand Government has sent two desalination units and water containers to the areas Funafuti and Nukulaelae where a state of emergency has been declared.
Red Cross spokesperson Andrew McKie says water from the desalination units produce up to three litres a minute but they are only a stop-gap measure.
It will be augmented by water being transported from Funafuti by the Tuvalu government.
Mr McKie says while authorities are looking for long-term solutions, the Red Cross is helping people prepare to harvest rainfall when it eventually comes.
New Zealand Foreign Affairs Minister Murray McCully says some areas of Tuvalu were down to two days' supply of drinking water.
He says the Government is also watching the situation in other parts of the Pacific, particularly Tokelau, where there are also severe water shortages.
Mr McCully says regional weather patterns may mean that rainfall is quite low for some months ahead.
The minister told Radio New Zealand's Morning Report programme on Tuesday the situation will also have a severe impact on crops and a food shortage is likely at some stage.
Mr McCully says unless there is some rainfall, they will be dealing with the situation for quite some time.