The Italian government and Lega party are pursuing a hardline policy on migration saying that Italy could not remain Europe's "refugee camp" while neighbouring countries close their borders and defend their frontiers with weapons.

The German charity boat Sea-Watch has entered Italian waters with 42 migrants aboard despite being ordered by Rome's authorities to stay out, the Sea-Watch press office reported.

According to the ship's press office, the captain had decided to head to the island of Lampedusa because the situation on board was "now more desperate than ever" and that he was allowed to enter these waters under maritime emergency law.

Meanwhile, right-wing Deputy Prime Minister Matteo Salvini has called the NGO boat a "pirate ship", emphasising that the rescued migrants aboard should go to the Netherlands and Germany.

The report comes after Italy passed a security and migration decree earlier in June that aims to curb the activity of migrant rescue ships operated by humanitarian groups. The nation's ports have remained closed to such boats since last summer.

The discussion about which country should accept migrants rescued at sea has been at the core of EU arguments over migration. Over the last several months, a number of NGO vessels have been stranded because ports were being closed to them.

European countries have been facing the worst migration crisis in recent history for around four years now. Italy, with Spain and Greece, have been the countries most affected because they serve as the main entry point for illegal migrants who reach Europe by sea.