UPDATE: Nauru says it has changed procedures for Australians applying for visitor visas after an unnamed ABC journalist ‘dishonestly’ entered the country as a tourist and failed to declare they were media.
On Friday morning, airline staff told callers the announcement was made by Nauru’s justice minister David Adeang on Thursday.
The move comes as Prime Minister Malcolm Turnbull meets his New Zealand counterpart John Key in Sydney today.
Nauru Airlines check-in staff at Brisbane airport last night informed Australian passport holders for this morning's 1am flight ON002 that their visas were no longer valid.
SBS has contacted representatives of the Nauruan government for comment but they have not responded, however the offical Twitter account of the Republic of Nauru just posted a tweet stating that visas have not been revoked.
Nauru hosts one of Australia's two off-shore asylum-seeker detention centres.
In January 2013, the Nauruan government increased journalist visa application fees from $200 to $8000, even if the visa was rejected.
The visa announcement comes as a stand-off over between doctors and the immigration department continues over discharging asylum seeker baby “Asha” from a Brisbane hospital.
Immigration minister Peter Dutton yesterday said the infant would be returned off-shore once she had recovered from wounds from a boiling water accident on Nauru.
Doctors are refusing to release the one-year-old until a "suitable home environment is identified".
Hundreds of people have held vigils and rallies since last Friday in support of letting the child stay in Australia.
Nauru Airlines is advising callers the ticket refunds are available for those affected.