The tiny Pacific nation of Tuvalu has declared a state of emergency due to severe water shortages, prompting New Zealand to airlift in fresh supplies, officials in Wellington said on Monday.

New Zealand Foreign Minister Murray McCully said an air force transport plane carrying containers of water and two desalination units arrived in Tuvalu on Monday.

"Tuvalu has declared a state of emergency relating to water shortages in the capital, Funafuti, and a number of outer islands," McCully said in a statement.

He said New Zealand officials were working with aid agencies including the Red Cross to ease the crisis in Tuvalu, one of the world's smallest independent nations with about 10,500 residents.

A Red Cross situation report released last week said the former British colony relied mostly on rainwater, which had been scarce this year because of a La Nina weather pattern across the Pacific.

La Nina causes extreme weather, including both drought and floods, and was blamed for deluges in Australia, Southeast Asia and South America over late 2010 and early 2011.  -AFP