Foreign Minister Stephen Smith says the deportation of an Australian publisher from Fiji is totally unacceptable.
He has accused the Pacific nation's government of trying to "muzzle freedom of speech".
Russell Hunter, 59, the managing director and publisher of the Fiji Sun newspaper, arrived in Sydney today after being put on a flight from Fiji's Nadi international airport.
Mr Hunter said he believed his newspaper's reports about alleged tax evasion involving Mahendra Chaudhry, a minister in Fiji's interim government, may have been the catalyst for his deportation.
"We were expecting it," Mr Hunter told reporters at Sydney Airport.
Australia has protested against the deportation by contacting the Fiji government and called on it to respect the rights and civil liberties of all citizens and residents.
Fiji is led by an interim government after military leader and self-declared prime minister Commodore Frank Bainimarama seized power in a bloodless coup in December 2006.
Australia disapproved of the military takeover and suspended some defence ties and aid to Fiji in response.
Mr Smith said the deportation of Mr Hunter was another act in a pattern of disturbing behaviour since the coup.
"The fact that the Fiji authorities detained and removed an Australian citizen without any advice to the Australian government or providing consular access is totally unacceptable," he told AAP.
"This would appear to be another move by the illegal Fiji interim government to muzzle freedom of speech.
"This is another act in a disturbing pattern of behaviour since the coup of December 2006 which has resulted in the severe erosion of fundamental human rights and the rule of law in Fiji."
Officials from the Department of Foreign Affairs and Trade spoke to Mr Hunter upon his arrival in Australia and have reported he is in good health.
"(He has told them he) was not mistreated by Fiji authorities, but was given no explanation for his deportation," Mr Smith said.
Mr Smith said the Fijian government had been unable to give the Australian High Commission in Suva any information about Mr Hunter's location or status, or any reason for the deportation, when they had sought access to him.
"This morning our High Commissioner to Fiji, Mr James Batley, made a strong formal protest to the interim government about the deportation," he said.
"I call on the Fiji interim government to respect the civil liberties of all citizens and residents and hold elections by the first quarter of 2009, consistent with the constitution and laws of Fiji, and as per its commitment to Pacific Islands Forum leaders (last year)."