The Pacific Islands Forum Secretariat says that while Nauru has stated its concerns about media reporting, the Forum has always stood by the principles of free and open media.
The statement was made in response to Nauru, which is hosting this year's Forum meeting, refusing to grant any visas for journalists from Australia's public broadcaster, the ABC.
The ABC planned to send someone as part of a three-person Australian pool to the September meeting.
But Nauru's government blamed the ABC for interfering in domestic politics and harassing its president, bias and false reporting, among other allegations.
The Forum Secretariat said while it supported media freedom, the press also had a responsibility to be factual in its reporting.
The Secretariat said it vigorously defends the right of any sovereign country to make its own decisions about the ways in which it chooses to govern, and it is committed to working with government of Nauru and the media to ensure the best possible outcome.
ABC's head of news said yesterday they were outraged by the ban and did not intend to vacate their position in the media pool.
There have been calls for other media organisations to boycott the Forum in response to the ban.
The 49th Pacific Islands Forum and related meetings is being held from September 3rd to the 6th.