The Tongan government said its newly certified MA60 aircraft was safe despite regional authorities not being involved in its certification.
The MA60 is due to be in operation this month after being grounded for over a year.
The aircraft was gifted by China in 2013, flew domestically in August of that year before the New Zealand government objected.
They called for the MA60 to be certified by an international recognised certification authority, suspending some aid and issuing a travel advisory for Tonga over safety concerns.
The acting CEO of Tonga's Ministry of Infrastructure, Kisione Taufa, said the MA60 had now been certified after examinations by Chinese inspectors.
He said New Zealand and the Pacific Aviation Safety Office were not a part of the certification process.
But Mr Taufa says the aircraft is safe.
"We believe so but at the same time, just to make it clear for the public, it is just like an annual examination for a car. We do it once and at the same time the maintenance and operation wiill be a job for the operator but if there is an issue we step in and check whether it's OK and safe for the public."
Meanwhile CEO of Real Tonga airline, Tevita Palu, said the government should communicate with New Zealand to ease any concerns they might have over domestic air safety.
Mr Palu said Tonga's civil aviation authority has certified the MA-60 and recently implemented changes to Tonga's Civil Aviation act to align standards with New Zealand's.
He said he hoped the country could soften its stance.
"The Government of Tonga should do what they are supposed to do and clarify these issues, if they have any issues or clarify any concerns. I think that's a role that government should confirm what's been done but from the airline's point of view, we go through the process as required," said Tevita Palu.