Transparency International Papua New Guinea has called for countries like New Zealand to help track proceeds of corruption in PNG that have been accrued abroad.
The call comes as the Asian Development Bank estimates that PNG's investment in Australia has reached US$1.2 billion.
TI PNG's Lawrence Stephens says the pattern of Papua New Guinean officials acquiring property and bank accounts well beyond their official earning capacity extends further than Australia.
He says there are also many questionable investments in New Zealand, Fiji, Vanuatu, Samoa and Solomon Islands.
"And we think that action could be taken in the countries that I've spoken of by ordinary people simply demanding that the laws be looked into, strengthened, if neccessary changed, so that people don't just walk off with millions from one country and plonk it down, aided and abetted by the slack laws of another country."