A much-anticipated aid flight is finally on its way to Tonga and will arrive with food and water in a few hours. 

The Royal NZ Air Force's Hercules aircraft left Whenuapai Airbase, in West Auckland, about midday and is on track to touch down about 4pm. 

The aircraft has humanitarian aid and disaster relief supplies, water containers, kits for temporary shelters, generators and hygiene and family kits. 

It comes after a volcanic eruption and subsequent tsunami devastated much of the country and resulted in the deaths of three people. 

A RNZAF Hercules has left for Tonga today. Image / Flight Radar 

The Hercules is also taking communications equipment that will be vital at the moment, given 

Foreign Affairs Minister Nanaia Mahuta said: "The delivery of supplies will be contactless and the aircraft is expected to be on the ground for up to 90 minutes before returning to New Zealand." 

The aid flight was due to arrive earlier this week. However, thick ash on the runway prevented any planes from landing safely at the international airport. 

Hundreds of people turned out to the runway to help clear away a thick layer of ash and debris seen all over the main island of Tongatapu, where the capital city of Nuku'alofa is. 

Damage in Pangai, in Ha'apai, Tonga. Photo / Haloti Ulufonua 

Two Navy ships from New Zealand are also set to arrive - one of them expected to be in Tongan waters later today, which is earlier than expected. 

The HMNZS Wellington is carrying hydrographic and dive personnel, as well as a Seasprite helicopter, to help with supply delivery. 

Its first task will be to check shipping channels and wharf approaches to the island kingdom's port to make sure vessels can go alongside. 

Minister of Defence Peeni Henare said the crew will also check the structural integrity of the wharf. 

An update on the situation on the ground in Tonga – as well as New Zealand's response to the disaster – is expected this afternoon. 

How you can help: To donate to help the people of Tonga, go to: New Zealand Red Cross.