Breakfast food, gardening tools and outboard motors are among the items desperately needed in Tonga following the devastating eruption and tsunami.

It has been eight days since a violent volcanic eruption and tsunami hit the island nation and relief supplies have begun to trickle in, but RNZ Pacific reports there is still widespread shortages of freshwater, food and communications across the country.

At the weekend the Tongan government said 85 per cent of its population had been affected by the disaster.

The Aotearoa Tonga Relief Committee is trying to work out how to get donations of essential supplies to Tonga from Auckland, and has made an appeal for more containers.

Local MP and group co-chair Jenny Salesa says she spoke with Tongan Prime Minister Siaosi Sovaleni yesterday, saying "there's so much that Tongan's need".

Sovaleni told her gardening tools and supplies were top of the list of items needed to keep people fed and make a recovery.

"They expect a lot of the gardens [with food in] now are probably not going to last very long because of that ash that is on top of everything," so a big effort would be needed to replant, she says.

Many of the country's boats were destroyed by the tsunami inundation, and Sovaleni had also asked for boats and outboard motors.

Breakfast food for children was another request, and Salesa says a $50,000 donation from Foodstuffs NZ will be used towards that.

Supplies gathered in Auckland by the Aotearoa Tonga Relief Committee will begin to be sent to Tonga this week. Photo: RNZ / Lydia Lewis.

The relief committee has held a donation drive at Mount Smart stadium in recent days, and say many Tongan New Zealanders have donated, and they now have enough to fill 25 containers.

The group has appealed for more containers, to send the goods in. Matson Shipping has donated 15 containers - but they hope more will be donated, and more containers can be filled in other regions outside Auckland.

Meanwhile the New Zealand navy's largest ship, the HMNZS Aotearoa, arrived in the capital Nuku'alofa last week to help, and has been desalinating water for drinking.

The ship's commanding officer Captain Simon Griffiths says clean drinking water is still a problem right across Tonga, and their new supplies are being distributed widely, with the Tongan navy taking it to islands to the north.

"We've been here two and a half days in Nuku'alofa, and in that time we've managed to offload over 260,000 litres of water and all our cargo. Given Covid protocols, that cargo has gone into 72 hours of quarantine, it's there on the jetting waiting to be used and it will clear that quarantine later today."

Clean up of the ash and debris is well under way, but some areas of the coast have suffered badly.

Time and tides are naturally beginning to clear some of the debris and ash from the top of the sea, which is helping Tongan ships that had initially been having trouble moving between islands.

"Commercial boats and barges are operating, now," says Griffiths.

Two New Zealand C-130 Hercules have also dropped off supplies, and other international assistance is on the way, with ships on the way from Australia, Japan, the US, and the UK, and a Fijian Navy ship already in Tonga helping.

The HMNZS Wellington is already carrying out dive and surveying work in the harbour and outer islands, and The HMNZS Canterbury is on its way to offer engineering supplies, says Griffiths.

"Full recovery will take a long time."

RNZ.