Mr McCully said the cyclone had caused "extensive and widespread devastation" in the Pacific country, taking lives, destroying homes and infrastructure.
"New Zealand is committed to supporting the Government and people of Fiji as they respond to this disaster and this is reflected in the further deployments we are announcing today."
The minister said it was one of the most damaging cyclones in Fiji's history and this was reflected in the scale of New Zealand's response.
New Zealand has already contributed $2 million in aid to Fiji since the cyclone struck on the weekend, killing at least 29 people.
The Defence Force's C-130s were delivering relief supplies to the country and the P-3 Orion was carrying out reconnaissance flights.
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