Children and sick or vulnerable people are expected to be allowed off a German-flagged rescue vessel by Italy on Saturday but other migrants on board may be sent back into international waters despite worsening weather conditions.
The Humanity 1, run by German charity SOS Humanity and carrying 179 migrants, has been requested by Italian authorities to come the port of Catania, its press officer told AFP.
The Humanity 1 is one of four humanitarian ships off Sicily which have requested permission to bring those rescued to safety in Italy as conditions at sea worsen in bad weather.
So far it is the only one that has been ordered to enter the harbour.
But the charity said it has not officially been assigned a port, an omission that leads it to believe not everyone will be allowed off.
Interior Minister Matteo Piantedosi said Friday that vulnerable people would be let off the Humanity 1, after which the ship would have to "remove" the remaining migrants from Italian waters.
"We fear that authorities will just let (us) disembark emergency cases and children, perhaps minors," the ship's press officer Petra Krischok said in a statement.
"We fear for the protection rights of the people who were rescued from distress at sea and all need protection," she said.
Italy's new far-right government, which was sworn in last month, has vowed to crack down on boat migrants coming from North Africa to Europe.
On Saturday, Piantedosi said the government would not "back pedal" on its humanitarian obligations, but those who do not "qualify... must leave our territorial waters and been taken care of by the flag state" -- a reference to the national flags under which the vessels sail.
Two of the charity boats -- the Humanity 1 and Mission Lifeline charity's Rise Above -- sail under the German flag.
The other two -- SOS Mediterranee's Ocean Viking and Doctors Without Borders' Geo Barents -- are registered in Norway.
The four vessels are carrying over 1,000 people saved in the Mediterranean.
The Norwegian foreign ministry said Thursday it bore "no responsibility" for those rescued by private Norwegian-flagged ships in the Mediterranean.
Mirka Schafer, SOS Humanity's advocacy officer, said the Italian government's decision to only take some people was "undoubtedly illegal".
"The survivors fled Libya, where they were exposed to human rights violations such as torture. As refugees, they are clearly in a vulnerable state, some of them visibly traumatised.
"Those rescued must be allowed to go ashore immediately, where their medical and psychological care can be ensured, and they can exercise their right to apply for international protection," she added.
'Lots of babies'
There were "lots of babies" on board the Rise Above which needed to immediately be provided with a safe port, Hermione Poschmann from Mission Lifeline told AFP.
The youngest of the 42 minors it is carrying are just seven and 10-months old.
The ship was off Catania after seeking shelter from bad weather. The 25-metre-long vessel "is a small, fast responder, not made for a long stand-off", Poschmann said.
The ship usually transfers those it rescues to the bigger charity vessels, but they have no space for them.
A photographer on the Ocean Viking, run by SOS Mediterranee, told AFP conditions at sea "are worsening, and we are expecting more rain".
"Those on board are not well because they are sea-sick, children included", he said, adding that there were 57 minors among the 234 migrants.
The Geo Barrents, run by Doctors Without Borders and currently carrying 572 rescued people, said Saturday it had also entered Italian waters to seek shelter "after requesting and receiving permission from the authorities".
"We have been waiting for more than 10 days for a safe landing place," mission head Juan Matias Gil said.