A German charity ship carrying 400 rescued migrants off the Italian coast is waiting for officials to give it permission to land.
The Sea-Eye 4 picked up the migrants from rickety wooden boats in international waters off Libya's coast in six rescue missions over four days, officials said.
It headed north towards Palermo but is awaiting permission to land with the migrants.
This follows months of wrangling between charities running rescue boats and the Italian authorities.
Permission normally takes four to 12 days, said an official with Sea-Eye, a sea rescue charity.
Within sight of Italy, those on board – including 150 children and pregnant women – are becoming increasingly anxious, said Sea-Eye spokeswoman Sophie Weidenhiller.
About 25 people need medical attention.
“They keep asking us when we can land. We just tell them we don’t know,” Ms Weidenhiller said.
Sea-Eye has accused the Italian authorities of obstructing the work of rescue ships in the area.
The UN says 685 people have died already in 2021 trying to cross the Mediterranean, the highest number since 2017.
More than 2,000 people died in 2015, at the peak of the migration crisis.