Spain has offered to take in a humanitarian ship stranded in international waters with 629 refugees aboard, prompting Italy’s new anti-establishment government to claim victory in its bid to “stop the death boats.”

In a move reminiscent of Australia’s contentious asylum seeker policy, Italy’s newly sworn-in, popularist government on Monday refused to allow the refugee-laden ship to dock at its ports.

The decision by Italian interior minister Matteo Salvini, who is also head of the far-right League party, represented an opening gambit to make good on his electoral promises to halt the flow of migrants into the country.

Days after assuming office, Mr Salvini issued a warning to people smugglers in a statement that drew direct comparisons with former Australian prime minister Tony Abbott’s “stop the boats” rhetoric.

“Every life is sacred. To save lives you have to stop the departures of these death boats, which is a lucrative business for some and a disgrace for the rest of the world,” he said last week.

After Italy had refused to let the Gibraltar-flagged Aquarius ship, whose passengers include 11 children and seven pregnant women rescued off the coast of Libya on the weekend, to dock, the European Union and the UN refugee agency called for a swift end to the stand-off.

The ship had sailed north towards Italy but Mr Salvini said it should go to neighbouring Malta instead.

Malta refused, saying it had nothing to do with the rescue mission, which was overseen by the Italian coastguard.

The tiny island nation with fewer than a half a million inhabitants says it already accepts more refugees per capita than Italy, which has taken in more than 600,000 boat migrants since 2014.

“Victory!” Mr Salvini tweeted after Spanish Prime Minister Pedro Sanchez, a socialist who took office just over a week ago, gave instructions that the ship be allowed to dock in the eastern port of Valencia.

Mr Salvini says he wants to ‘stop the death boats’. Photo: Getty

“To politely raise one’s voice pays off,” Mr Salvini told a news conference in Milan. “It’s something Italy hasn’t done for many years.”

Italian Prime Minister Giuseppe Conte said on Facebook that Spain’s offer meant Italy was “no longer alone” and now it was time to make EU asylum rules “more fair for everybody”.

The stand-off will help Mediterranean EU states like Italy, Spain and Malta who have been on the geographic frontline of the migrant influx to raise pressure on EU partners further north ahead of a June 28-29 summit that will, in part, consider changes to EU asylum law to better share the burden of incoming migrants. More than 1.8 million have entered Europe since 2014.

SOS Mediterranee, the charity co-operating the migrant ship, said it was awaiting instructions about where to disembark from Italy’s coastguard, which coordinated the sea rescues.

“Several (migrants) need medical assistance, which requires a rapid solution,” Doctors without Borders, which runs a medical clinic on the Aquarius, said in a statement.

Valencia is almost three days’ voyage for the Aquarius, while Italy and Malta are just hours away.