A fire at a water treatment plant in the Maldives has cut off drinking water to the capital of the Indian Ocean country.
About 100,000 residents in Male have lost access to drinkable tap water, the government says.
The authorities are providing bottled water free of charge. Scuffles were reported as residents fought to buy up water supplies in shops.
India says it is airlifting drinking water to the low-lying island chain.
Delhi has despatched two ships with spare parts for the plant, said Syed Akbaruddin, an Indian foreign ministry spokesman. The first Indian plane carrying bottled water arrived on Friday.
"Last night, the Maldives foreign minister contacted us saying they were facing a grave emergency," Mr Akbaruddin said.
"For the next seven to eight days they are going to face extreme difficulty with water so they requested all assistance."
The Maldives government has also appealed to Sri Lanka, China and the US for help.
According to the UN, there are no permanent rivers or streams on the Maldives, and the country finds it difficult to obtain suitable drinking water.
The main supply of drinking water in the capital is provided by desalination plants.
Hotels and resorts are not affected by the shortage, as they have their own water treatment facilities.
The Maldives economy revolves around tourism, which generates about 30% of the country's gross domestic product (GDP).
The country is also vulnerable to a rise in sea levels associated with climate change, as none of its islands are more than 1.8m (6ft) above sea level.