The Sydney Morning Herald reports that Australian officials believe the Fiji military is responsible for the death threats against the Australian high commissioner.
This comes as Australia's high commissioner in Suva, James Batley, says he is disappointed that the interim government has rejected his request for Australian police protection.
Fiji's interim administration says the request was denied because the responsibility for the safety of diplomatic missions rested with it.
Fiji police have been investigating two death threats made this month.
According to Fiji media, a statement on the issue was expected from Fiji's Police Commissioner Esala Teleni today but that has now been cancelled..
Australian officials say the threat appears to be politically motivated.
Australia and New Zealand have been critical of the 2006 military coup.
Last year, the New Zealand high commissioner was expelled.