The Norfolk Island Chamber of Commerce is calling for an urgent change in direction by Canberra or the island risks becoming a "failed state".
In a statement it said the Australian takeover in 2016 had clearly failed because the economy is going backwards quickly.
It said a report compiled for the Australian government more than 10 years ago had forecast that taking direct control of the autonomous island would damage its fragile economy.
Chamber spokesperson, Glenn Christian, said tourism, the main business on Norfolk, has slumped seven percent in each of the last five years.
He said the pressure on businesses is clear from his own experience in the IT sector.
"All of my customers have a presence in the tourism industry, whether they are running hotel accommodation, motel accommodation, whether they are selling, for example, souvenirs for tourists etc. I talk to my customers and universally they tell that visitor numbers for Norfolk are the worst they can remember.
"They are terrible and that's reflected in my business as well."
Canberra's administrator on the island, Eric Hutchinson, has so far not responded to our requests for comment.