The Italian government has progressed a law to impose fines of up to €1 million ($1.12 million) for organisations and groups who rescue drowning refugees.
The law has been heavily promoted by far-right Interior Minister Matteo Salvini.
The Italian Senate passed the law earlier this week with 160 votes in favour and 57 against.
The controversial law was passed by Italy's lower house earlier this year, and it is waiting to be ratified by Italian President Sergio Mattarella.
Captains bringing in "unauthorised" rescued refugees will face arrest, and a fine of between €150,000 and €1 million ($167,988-$1.12 million).
The UN's refugee agency UNHCR has expressed concern about this hardline approach, saying it could hinder or even prevent rescue efforts at sea.
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Charity Medecins Sans Frontieres (MSF) Italy condemned the move, saying it will inflict suffering and risk the lives of vulnerable people.
MSF Italy President Claudia Lodesani said: "[This law is] like fining ambulances for bringing patients to hospital."
The move is an "abuse of power", Sea-Watch, a charity that leads rescue expeditions in the Mediterranean Sea, said, adding that it "creates a state-led culture of defiance of international maritime laws and conventions that protect human life at sea."
The charity has already run into trouble with Italian authorities who arrested one of its captains, Carola Rackete, after she rescued 40 stranded refugees.
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Rackete is currently being investigated for allegedly aiding and abetting "illegal migration", despite an Italian judge allowing her to walk free, ruling she was "doing her duty to save human lives".
Currently, it is estimated that around 70 million people are displaced as a result of conflict.
According to the International Organisation for Migration some 840 refugees and migrants have died while trying to complete the perilous journey across the Mediterranean Sea so far this year.cc