Tongans are welcoming the deployment of Australian and New Zealand troops to Nuku'alofa.

150 troops are due to arrive in the Tongan capital later today, following riots this week which have left eight people dead. The contingent is led by 60 New Zealand Defence Force personnel, and includes up to ten New Zealand Police. The New Zealand led force will be supplemented by more troops and police from Australia.

Tongan Times editor Osi Maama says while people are pleased to see the troops arrive, there is a sense of uncertainty about the future of Tonga. He says he does not expect any backlash against the overseas troops when they arrive.

Prime Minister Helen Clark announced the move during a media conference with her Australian counterpart John Howard in Hanoi, where they are attending the Apec summit. She says countries like ourselves and the Australians have a responsibility to help out when things like this happen. Miss Clark says fragile states are vulnerable to the drug trade, problems with the financial system and even terrorism, and that's something nobody wants in the Pacific.

The contingent's Hercules was about an hour late leaving Whenuapai airbase this morning. It eventually got off the ground around 9am.

Australia is sending around 50 military personnel and more than 30 Federal police as part of the New Zealand-led deployment. Miss Clark says the New Zealand personnel will also find out from Tonga's police what might be needed in terms of ongoing assistance in the short and medium term. The Ministry of Foreign Affairs and Trade is also sending two additional consular staff to bolster the High Commission.

A large portion of Nuku'alofa's business district was destroyed by protesters who set buildings alight and overturned cars earlier in the week. At least eight people have been killed in the violence.