The International Organisation for Migration expects a substantial number of Afghan asylum seekers on Nauru to be granted refugee status.
The IOMs Canberra based spokesman, Denis Nihill, says the Australian Government's decision to grant 15 of them refugee status is just the start.
"It's only the beginning of the total review of the Afghan case load. The decisions are going to be released as they become available so it doesn't really give any indication as to what that total number will be. I know it's going to be substantially higher."
The decisions are the first to be handed down as a result of a re-examination of 180 cases on Nauru due to changed conditions in parts of Afghanistan.
The Australian Immigration Minister, Amanda Vanstone, says most of the 15 will be offered resettlement in Australia.
Additional decisions have been made denying refugee status to three people who have now been encouraged to return home.