UN ALARM
Salvini said Libya had offered to take back the migrants aboard the Ocean Viking and said Open Arms should go to Spain.
Doctors Without Borders has ruled out taking migrants to violence-plagued Libya, saying migrants are routinely tortured and abused there. Open Arms has called for the European Union to coordinate the re-distribution of the migrants around the bloc.
The United Nations' refugee agency called on European governments to intervene, warning that storms were approaching.
"To leave people who have fled war and violence in Libya on the high seas in this weather would be to inflict suffering upon suffering," said Vincent Cochetel, UNHCR Special Envoy for the Central Mediterranean.
"They must be immediately allowed to dock, and allowed to receive much-needed humanitarian aid."
Spain said Italy should deal with the immediate care.
"International law states that a rescue takes place in the closest safe port. Without doubt, right now that means Italy. If it was us, we would do it," Spain's acting development minister Jose Luis Abalos told Telecinco television on Tuesday.
However, he also said Europe needed to forge a "wider" policy to handle migrant arrivals from Africa.
Italy has taken in more than 600,000 boat migrants since 2014, but new arrivals have fallen sharply over the past two years, with the decline accelerating over the past year.
Latest figures say 4,265 migrants have reached Italy so far in 2019, down 78 percent on the same period in 2018 and down 96 percent on 2017 levels. ($1 = 0.8915 euros)
