Drought-stricken Palau could dry up completely this month, officials warned on Monday as the Pacific island appealed for urgent aid from Japan and Taiwan, including shipments of water.

The tiny country of about 18,000 people declared a state of emergency last month, the latest Pacific island nation to do so as one of the worst ever El Nino-induced droughts in the region worsens.

"We're still in the state of emergency, there's a sense of urgency to address the crisis," said a government spokesman as the National Emergency Committee met to discuss strategy.

An NEC report prepared for President Tommy Remengesau offered a bleak outlook for the already-parched country.

"Based on the current water level and usage rates, and assuming conditions persist unabated, a total water outage is likely to occur in the next two to three weeks," it said.

Access to tap water is already rationed to three hours a day or less in the capital Koror and schools are only open half days because they cannot give students enough to drink.

"The NEC has been in contact with the governments of Japan and Taiwan regarding support of materials and equipment, as well as direct shipments of water as necessary," it said.

The Japanese embassy in Palau confirmed it had received a request for assistance and discussions were ongoing about what form it would take. The nature of what type of assistance and in what volume is expected to be finalized as soon as possible," it said in a statement.

Palau also expects help from Taiwan.

The NEC report added that the US military had been asked to supply portable water filtration systems to alleviate the increasingly desperate situation.

The US National Oceanic and Atmospheric Administration said the El Nino weather pattern - associated with a sustained period of warming in the central Pacific which can spark climate extremes - was unlikely to ease before the second half of the year.

The Marshall Islands and the Federated States of Micronesia have also declared states of emergency.

In Koror, bottled water has become scarce as people stockpile dwindling supplies.

"There are no words to describe the level of stress, worry and burden of hauling water from one place to another," said resident Rolynda Jonathan. "Every morning we struggle to shower, clean up and prepare for the day with the limited amount of water we have."