INDONESIAN authorities say there's little hope of finding more survivors from an asylum-seeker boat that sank off the coast of Java, leaving more than 50 people dead or missing.
The search for survivors, and the dead, resumed on Sunday morning but efforts are being hampered by rough seas.
Twenty-one people, including seven children, have so far been confirmed dead while more than 30 remain missing, Rohmali, the head of the search and rescue agency in area where the incident occurred, said on Sunday.
Just 28 asylum seekers have been found alive since the boat, which was carrying about 80 people from Lebanon, Iran and Iraq, sank on Friday morning.
"If there's any hope, it will depend on today's search," Rohmali told AAP.
"But if there's no progress today or if the condition is as harsh as yesterday - waves yesterday were five-metres high - then we may have to stop the search and only observe.
"We don't want our team to be the casualties as well."
It's expected some of the survivors will be sent to immigration detention centres.
However, an Indonesian immigration official in Sukabumi where the majority of those rescued were being held has confirmed to AAP that the Iraqi and Lebanese embassies had made contact and were already in the process of arranging for their citizens to be deported.
"We've contacted our Immigration Directorate General in Jakarta asking which immigration detention centre to place them," Yayan Indriana, the head of Sukabumi Immigration Office, told AAP on Sunday.
The official said the preference was to send the asylum seekers to Tanjung Pinang in the Riau Islands or to Medan, on the island of Sumatra.
"There are also people from Iraq and Lebanon embassy who came to see me asking to deport their citizens. As long as they take care of all the documents needed and the ticket, we welcome them to deport their citizen," she said.
There have been conflicting reports about how the tragedy unfolded, with some of the survivors claiming they placed more than 10 calls to Australian authorities to say their boat was sinking, beginning on Thursday, but that no help was sent.
"We called them and we told them we're sinking, we need anybody to help us," 28-year-old Abdullah al Qisi said on Saturday..
"And they were telling us 'we're coming, we're coming' and they didn't come," he said.
But immigration minister Scott Morrison, who delayed commenting on the sinking until late on Saturday, said Australian authorities did not receive a call about the vessel until Friday morning, which placed the stricken boat about 25 nautical miles off Indonesia.
Mr Morrison said Rescue Co-ordination Centre Australia maintained co-ordination of the search and notified the Indonesian rescue agency, BASARNAS.
An all-ships broadcast was issued by Australian authorities, but a merchant ship and a border protection aircraft were both unable to find the vessel.
A spokesman for BASARNAS also says his office was not advised of an incident involving an asylum-seeker boat until 8am local time on Friday.
It appears, however, that messages were slow to get to local authorities closer to the scene of the incident.
A police official from the district of Cianjur near where the boat sank has said his officers were only alerted to the incident after bodies were discovered floating in an estuary on Friday morning.
The latest tragedy in waters between Indonesia and Australia - the first known fatal attempted crossing since the election of the Abbott government - comes amid an increase in tensions between Canberra and Jakarta over the asylum-seeker issue.
Prime Minister Tony Abbott and Indonesian President Susilo Bambang Yudhoyono will hold talks on Monday, with asylum-seeker policy expected to be at the top of the agenda.
