Koror (Palau) (AFP) - Palau became the latest Pacific island nation to declare a state of emergency Wednesday, as the region struggles with an extreme drought that forecasters warn will not ease for months.

President Tommy Remengesau said rainfall in the capital Koror over the past four months was the lowest recorded in 65 years and the city's only dam had dried up.

He said Koror's only other source of drinking water, the Ngerikiil River, was down to 19 percent capacity.

"According to the... weather report, drought conditions exist and will continue to exist for all islands and atolls of Palau, with below average rainfall projected for the next two to three months," he said in a statement.

Water rationing was introduced in Koror earlier this month, with residents only able to use taps for six hours a day.

The US National Oceanic and Atmospheric Administration (NOAA), which provided the forecast, last week said an El Nino weather system was behind the drought.

"One of the strongest El Nino events in recorded history remains entrenched across the equatorial Pacific Ocean," it said.

The Marshall Islands and the Federated States of Micronesia have already declared states of emergency, while Guam and the Northern Marianas are also experiencing low rainfall.

Remengesau said basic government services such as hospitals, the fire department, prisons and power utilities could fail if the drought worsened.

The emergency declaration will give the president extra power to allocate funds to measures that will alleviate the problem, such as desalination units.

El Nino is the name given to a weather pattern associated with a sustained period of warming in the central Pacific which can spark climate extremes