Emergency officials in Tonga may use a Defence Service patrol boat to get assistance to the drought-stricken Ha'apai islands.
A high-level meeting on Tuesday gave the go-ahead for supplies and desalination units to be sent after it was revealed water supplies were just 20 percent of normal levels.
The director of the National Emergency Management Office Leveni 'Aho says machines would be sent today via ferry with the possibility of using a patrol boat as well.
Mr 'Aho says the struggle for water may continue for a while.
"The long-term forecast for the islands, it's not very bright. This will probably be with us for the next few months so no rain seems to be in the near future. There are also reports from other parts of Vava'u and northern islands of Niua approaching that sort of situation too."
Mr 'Aho says surveyors will be sent to Vava'u and the Niuas to assess the situation.
The Ha'apai Governor's Office says a desalination unit provided by the National Youth Congress has arrived and is helping ease the shortage.