By Phil Mercer BBC correspondent in Sydney

Australia is to double its annual aid budget to the South Pacific, which Canberra has described as "underdeveloped and insecure".

Australia led a military intervention in the Solomons last year

Most of the extra funds will go to the Solomon Islands and Papua New Guinea.

Australia is planning to send around 300 police and civil servants there to help fight crime and corruption.

It has embarked on a more interventionist role in the region since an Australian-led rescue mission to the Solomon Islands last July.

The problems faced by Papua New Guinea - crime, corruption and high rates of HIV/Aids - will pose the biggest challenge so far for Australia's regional interventionism.

The government in Canberra announced in its annual budget that aid to PNG will increase by a quarter, to more than $US300m a year.

Australia wants to make sure the money is not wasted.

For years, there has been concern and dissatisfaction at the way that some of the aid has been used.

Canberra's plans to send police officers and public servants to Papua New Guinea are on hold because of Australia's demand for legal immunity for its officers.

If and when the deal is signed, Australian police would be deployed to the troubled Highlands region, where tribal violence, highway robberies and serious sexual assaults are commonplace.

Under the proposal, Australians would take up senior positions in the judiciary and economic management.