The news organisation Al Jazeera says it went through the appropriate channels in its bid to visit Nauru and was still denied access.
Al Jazeera planned to report on the Australian-run asylum seeker detention centre there.
After nearly a year of trying to supply requested documents, Al Jazeera was told last week its application would not be approved.
Al Jazeera had been preparing its application to Nauru complete with the required US$5000 non-refundable fee for journalists.
The government has said the organisation didn't go through the proper channels, but Al Jazeera's Andrew Thomas denies this.
"We did go through the official procedures and processes as outlined by the government of Nauru in relation to obtaining a media visa. During that process we were told by a senior Nauruan official that no media visas were being approved and numerous attempts to clarify that having gone unanswered, we can only conclude that all media applications are being refused."
Al Jazeera says it will continue to try and contact the Nauru government for clarification so it can visit the island.
Amnesty International calls on Nauru to allow media in
Amnesty International says the refusal to allow in journalists to Nauru is just the latest evidence of a crackdown on freedom of expression.
Meghna Abraham says whatever Nauru is trying to hide, it can't be good if the authorities are so desperate to block all international media from visiting or reporting from the island.
Ms Abraham says amid allegations of ongoing abuse, including sexual assault, of asylum seekers it is all the more vital that media are neither barred nor silenced from reporting the truth.
She says Nauru must immediately allow the media in and repeal criminal sanctions that undermine the right to freedom of expression, as well as allow independent human rights monitors access to the country.