The Pacific nation of Vanuatu is preparing to permanently evacuate the entire population of one of its islands as thick ash spewing from a volcano kills crops, dirties water supplies and fouls the air.

The 10,000 or so people who remain on Ambae island have mixed feelings about the plans. Some who are badly affected by the ash are eager to leave while others are resisting losing their land and culture.

The island was temporarily evacuated last September when the eruption cycle began. This time, authorities are planning a permanent move.

Government spokesman Hilaire Bule told The Associated Press yesterday that he expects the Council of Ministers to approve a relocation plan by next week. Bule said the islanders would be offered residence on two neighbouring islands.

"It's not an easy decision," Bule said.

He said there were many details to work through, including providing schools and facilities to the displaced residents and negotiating land and new homes for them. Many people have close family and spiritual ties to the islands where they'll be relocated, Maewo and Pentecost, Bule said.

Traditional religion even has it that the islands are part of a family — Pentecost being the mother, Maewo the father and Ambae the son.

Most people on Ambae live a subsistence lifestyle by farming and fishing.

Already hundreds of people have moved to temporary shelters on parts of the island that are not so affected by the ash.

Ambae is about 400sq km and is one of about 65 inhabited islands in Vanuatu, which is home to 280,000 people.

Vanuatu sits on the Pacific's "Ring of Fire", the arc of seismic faults around the Pacific Ocean where earthquakes and volcanoes are common.

Brad Scott, a New Zealand volcanologist with GNS Science who has been seconded to help Vanuatu authorities, said more than one-quarter of Ambae has been severely impacted, with many traditional thatch roofs collapsing under the weight of the thick ash.