Immigration controls in Australia are so tough that asylum seekers are rejected on board naval warships at sea before being returned immediately, it emerged yesterday. Australian prime minister Tony Abbott says the EU must ‘urgently’ follow his lead to stop migrants dying in the Mediterranean as they seek a new life in Europe. Yesterday Italian prime minister Matteo Renzi said his country was ‘at war’ with migrant traffickers, describing them as ‘the slave traders of the 21st century’. Scroll down for video . The Australian Navy, pictured, is processing migrants' claims while at sea before returning them home . Australia has one of the toughest immigration policies in the developed world according to experts . Australian PM Tony Abbott, pictured, has said his country's immigration controls have been strengthened . EU leaders will hold a crisis summit in Brussels today to agree a strategy after up to 900 were killed when a fishing boat from Libya capsized. They are expected to double funding and equipment for EU border-patrol missions off the North African coast. But critics believe millions of impoverished Africans and Asians are happy to set off into the Mediterranean in leaky boats because they are confident humanitarian efforts will save them and speed them to their destination. Mr Abbott has insisted: ‘The only way you can stop the deaths is to stop the boats.’ Australia detains people on the Pacific islands of Nauru or Papua New Guinea while their asylum applications are considered, in order to avoid them absconding and staying on Australian soil while their cases are heard. Those on Nauru have the ‘opportunity’ to seek a life in Cambodia – which is paid by Australia to take them – while those in Papua New Guinea can stay there under a similar deal. Any who sneak past navy patrols to set foot on Australia are barred from staying for ignoring procedure, even if their asylum claim is genuine. But it emerged yesterday that Australian premier Mr Abbott’s immigration-control policy is even tougher than had been previously thought. It was revealed that officials rejected asylum claims of 46 Vietnamese aboard an Australian navy vessel – without setting foot on dry land – before the group was handed back to Vietnam last week. The screening aboard HMAS Choules is believed to have happened over a number of days after a boat was intercepted north of Australia. They were returned to the port city of Vung Tau, south of Ho Chi Minh City. Australia’s Vietnamese community leaders warned that the Abbott government would be ‘throwing people back to hell’ by returning the asylum seekers. There were reports last year that an asylum seeker from an ethnic minority hill tribe was badly beaten by Vietnamese government officials after being returned by Cambodia. And Amnesty International said that claims of persecution by the Vietnamese cannot have been adequately assessed while still at sea. Amnesty’s Graeme McGregor said: ‘These reports are extremely concerning and represent a fundamental violation of refugee rights. ‘Basic screening procedures at sea cannot be relied upon to make such life and death decisions. ‘Instead of digging itself deeper into disrepute by negotiating secretive deals to return asylum seekers, Australia should be helping those in need and identifying safe, practical ways for refugees to reach safety. The government has repeatedly excused its secretive boat turn-backs by trying to claim that they save lives. ‘The return of Vietnamese asylum seekers to the very country and government that they have escaped from exposes the truth about the government’s policies: that they do not save people, but repel people who may need our help.’ Immigration minister Peter Dutton refused to comment on the return of the Vietnamese but insisted people were not sent back to countries where they would face persecution. However, in a video to be shown to asylum seekers on Nauru, he can be seen urging them to take up the Australian offer for them to resettle in Cambodia. He tells the asylum seekers: ‘It is a fast-paced and vibrant country with a stable economy and varied employment opportunities.’
Migrant asylum claims are processed by the Australian navy while at sea .
Unsuccessful applicants are returned home without reaching dry land .
Up to 900 migrants are feared drowned after their boat to Europe capsized .
Australian PM Tony Abbott advised the EU  'to stop the boats'