More than 600 refugees and aid workers are stranded in a boat in the Mediterranean after both Malta and Italy refused to let the vessel dock.
Among those on board the rescue ship are 123 unaccompanied minors, 11 younger children and seven pregnant women, the German charity SOS Méditerranée says.
Italy's new interior minister, Matteo Salvini announced on Sunday that all Italian ports were closed to the rescue boat, called Aquarius.
Salvini, leader of the right-wing League party, promised voters a tough stance on immigration in the run up to the recent election.
He said Malta should accept the Aquarius, but the government in Valletta said those rescued fall under Italy's jurisdiction as they were picked up the migrants in Libyan waters.
Writing on his Facebook page, Salvini said: "Malta takes in nobody. France pushes people back at the border, Spain defends its frontier with weapons. From today, Italy will also start to say no to human trafficking, no to the business of illegal immigration."
Around 400 of those on board were rescued by the Italian Navy, the Italian coastguard and merchant vessels before being transferred to the Aquarius.
In defiance of Salvini, the mayor of Palermo, said he would allow the boat to dock in the Sicilian capital on Sunday night, however a journalist on board tweeted to say the boat had not moved since Sunday night.
Nick Romaniuk, search and rescue coordinator for the vessel, told the BBC Radio 4 Today show on Monday morning that those on board had been rescued in difficult conditions and were in need of medical attention.
He said: "We have doctors on board who are taking care of them but it's not definitive care so they do need to be disembarked as soon as possible so they can get the best treatment that they can."
SOS Méditerranée spokesperson Mathilde Auvillain said the boat had received orders to head north after a series of sea rescues and was now was awaiting "definitive instructions".
"Our objective is the disembarkation in a port of safety of the 629 people now on board the Aquarius – some we rescued yesterday night in difficult conditions," she said.
Anelise Borges, a correspondent for Euro News and NBC, said the situation on board was calm on Monday morning. In a video, she said: "People are slowly getting up and getting ready for their first meal and we are yet to learn which port they are going to be using to disembark. Still no news from Italian authorities."
The UN refugee agency in Italy has called on "states and actors involved" to "rapidly find solutions to allow migrants and refugees on board the Aquarius to disembark safely and quickly".