The UN High Commissioner for Refugees (UNHCR) said not enough is being done to save the lives of the rising numbers of African migrants trying to cross the Mediterranean to Europe.
A UNHCR spokesman made the remarks after it was reported that around 400 migrants were still missing yesterday after their boat capsized off Libya.
The Libyan coastguard said it expects more attempted crossings later this week, as the weather improves.
Hundreds of thousands of migrants have made the perilous crossing in recent years, fleeing poverty and conflict in Africa and the Middle East.
Hundreds more migrants, who were rescued from boats in the Mediterranean, were due to arrive in Sicily yesterday.
Almost 10,000 migrants have been picked up in recent days, and more boats are heading for the Italian coast.
Italy’s interior ministry has instructed officials throughout the country to be prepared to house the new arrivals, many of whom are children.
UN officials say more than 500 people have died since the start of the year, 30 times more than in the same period last year.
More than 280,000 people entered the EU illegally last year, many fleeing conflict in Syria and repression in Eritrea.
The Italian coastguard rescued 144 people from a capsized boat on Monday and launched an air and sea search operation in hopes of saving others.
Nine bodies have already been recovered, but no more survivors have been found since then.
Last year, 170,000 migrants crossed the Mediterranean to Italy and as many as 3,500 died while making the journey, officials say.
The Italian government’s maritime rescue operation was scaled back, amid concerns that it was encouraging migrant crossings, and a more limited EU border security operation took over.
However, the latest numbers show that the EU’s policy of deterring people is not working
The EU’s Frontex border agency said that people smugglers had fired shots into the air to warn away another coastguard vessel rescuing migrants.
The incident on Monday happened about 60 nautical miles off Libya after an Italian vessel and an Icelandic coastguard ship had rescued most of the 250 migrants on a tugboat. Frontex says the incident shows that traffickers are running out of boats.
EU migration commissioner Dimitris Avramopoulos told the European Parliament: “The unprecedented influx of migrants at our borders, and in particular refugees, is unfortunately the new norm and we will need to adjust our responses.”
Since the fall of Muammar Gaddafi in 2011, Libya has been without a stable government allowing trafficking networks to thrive. On Friday, humanitarian organisation Medecins Sans Frontieres announced it would operate a search and rescue mission in the Mediterranean between May and October.