European Union foreign ministers agreed on Monday (18 May) to set up a naval mission in the Mediterranean to target gangs smuggling people from lawless Libya to Europe – the first step to set up a military operation that would require a resolution from the United Nations Security Council to be fully operational.

The EU's foreign affairs chief Federica Mogherini said the decision taken at a meeting of foreign and defence ministers in Brussels would "disrupt the business model of smugglers and traffickers networks in Mediterranean".

The EU ultimately wants to capture smugglers and destroy their boats off the Libyan coast to help tackle the rising number of migrants fleeing war and poverty in North Africa, but many EU countries want UN authorisation to act.

"This is just the beginning of it, the decision to establish an operation means that now the planning, the operational planning starts," Mogherini said.

"I would say that there is a clear sense of urgency in this respect, also because we know very well that June is the beginning of summer, and in this operation seasons are important. And as summer comes, more people are travelling and we want to have, at least I'd like to have the operation in place as soon as possible if it has to deter traffickers and smugglers' organisations," she added.

Some 51,000 migrants have entered Europe by crossing the Mediterranean Sea this year, with 30,500 coming via Italy. About 1,800 have drowned in the attempt, the UN refugee agency says.

At an emergency summit in Brussels last month following the loss of hundreds of people aboard a single vessel, EU leaders agreed to "identify, capture and destroy vessels before they are used by traffickers".

Mogherini flew to New York this month to seek support for a draft resolution by Britain, France, Lithuania and Spain under Chapter 7 of the UN Charter, which allows the use of force to restore international peace and security.

Without UN authorisation, the EU's naval mission will not have the mandate to intervene in Libyan territorial waters and onshore in Libya to seize vessels. But EU diplomats say that the EU can start using ships and helicopters in the high seas to gather intelligence about people smugglers.

"The mission, its concept, was today agreed. There were no voices against it, the discussions continue. The next steps will be established more precisely when the legal basis is clarified, this too was discussed without any argument," German foreign affairs minister Frank-Walter Steinmeier said.

"If we want to take action in high seas, if we want to board, if we want to operate in Libya's territorial waters, then we need a resolution from the Security Council which we still don't have today," he added.

Austria said it would oppose the mission if it did not have a UN mandate.