"We take our responsibilities very seriously as a donor in the region and to Tonga, to make sure that where we are involved in an area like tourism that both New Zealand citizens and the citizens of any part of the world, including Tonga, are safe if they travel on an aircraft. We all recall with great sadness the death of those on the Princess Ashika." The Princess Ashika sank in Tonga in 2009, taking 74 lives.
He said he knew tourism was important and understood the frustration in Tonga's tourism sector, but if there was an air accident it would have serious, long term implications for tourism in Tonga.
The two Prime Ministers were also asked about aid and low-interest loans from China, which is increasingly overshadowing Tonga's historical donors.
Prime Minister Tu'ivakano was unrepentant about accepting that aid and low interest loans, and said there was nothing wrong with it.
"I guess everybody has noticed China is like the new guy on the block. When you look at small island developing states they are friends with everybody and not enemies with anybody."
He said China had a lot of money and its low interest loans gave small countries an option they could not afford otherwise, which helped development. "The two commercial banks here have very high interest. Nobody in Tonga could loan from the bank. I think if China can provide that for us, I wouldn't say no."
Mr Key said no country had a monopoly on aid and New Zealand had worked constructively with China's aid programme on some Pacific aid programmes.
Mr Key also met with Tonga's King today. He leaves Tonga in the morning to spend a day on Niue before returning tomorrow night.