ROME — Italian Interior Minister Matteo Salvini on Monday launched a fresh crackdown on charity ships which rescue migrants off Libya and bring them to Italy.

"The ports have been, and remain, CLOSED", Salvini said on Twitter, as his office released an eight-page directive on the laws regarding rescue operations - laws it said some aid vessels had been breaking.

The minister, who also heads up the anti-immigrant League party, has repeatedly declared Italian waters closed to NGO rescue vessels, leaving several of them stranded at sea in the past in a bid to force Europe to take its share of asylum seekers.

While he acknowledged in his directive that helping those who lives are in danger was a "priority", he warned that there must be "sanctions" for those who "explicitly violate international, European and national rescue regulations".

"Nor must the real risks that the group of migrants may conceal individuals involved in terrorist activities... be overlooked".

The "passage of rescue ships in Italian territorial waters" was "detrimental to the order and security of the Italian State", he said.

The directive was issued just hours after an Italian charity ship rescued 49 people off the coast of Libya, under the nose of the Libyan coast guard, before requesting permission to disembark the migrants in Italy.

NGO ships have drawn fire from Rome by attempting on occasion to stop migrants being taken back to crisis-hit Libya, which human rights organisations insist cannot be considered safe for repatriations.

‘Violation of maritime law’

"It has happened that ships... have come to the aid of migrants in non-Italian SRRs (Search and Rescue Regions) and have disregarded the orders of the competent SAR (Search and Rescue) authorities," Salvini said in the directive.

Ships rescuing migrants in areas of the Mediterranean that fall under Libyan responsibility, during operations not coordinated by the command centre in Rome, have no right to seek Italy as a port of safety, he said.

He accused the ships in question of "carrying out the rescue on their own initiative and then heading towards European maritime borders... in violation of international maritime law".

Salvini also took issue with charity ships that set sail for Italy rather than other ports.

"Nor are the Italian coasts the only possible landing places in the event of rescue events, given that the Libyan, Tunisian and Maltese ports can offer adequate logistical and health assistance... (and) are closer in terms of nautical miles".

Salvini, whose anti-migrant rhetoric has boosted him in the polls, has repeatedly vowed to find a way to ban all ships with rescued migrants from entering Italian waters.

He also insists Europe must do much more to help house asylum seekers.

Europe has been wrestling with divisions over how to handle the problem since the migration crisis of 2015 when more than one million people arrived on its shores, many of them fleeing conflict in the Middle East. — AFP