EU foreign and interior ministers are due to meet in Luxembourg to discuss the deaths of migrants trying to cross the Mediterraneanfrom Africa.
Some southern European nations say the EU's credibility is now at stake after last year's decision to scale back search and rescue efforts.
On Sunday, hundreds are believed to have drowned after their boat sank off the coast of Libya.
The UN says the North Africa-Italy route has become the world's deadliest.
The 20m (70ft) long boat was believed to be carrying up to 700 migrants, and only 28 survivors have been rescued.
A boat carrying coffins of the 24 victims found so far has just arrived in Malta, the Italian Coastguard says.
EU foreign policy chief Federica Mogherini said ahead of the foreign ministers meeting there was "no easy solution, no magic solution".
"We have a political and moral duty to exercise our role. The Mediterranean is our sea and we have to act together as Europeans. It is also [in] our interest, [in that] of our credibility; the European Union was built and is built around the protection of human rights, human dignity and the life of human people - we need to be consistent in that."
On Sunday, Italian Prime Minister Matteo Renzi said an emergency EU summit by the end of this week had to be a priority, adding trafficking was "a plague in our continent" and bemoaned the lack of European solidarity.
Maltese Prime Minister Joseph Muscat has told BBC Radio 4's Today programme that Libya is key to resolving the crisis:
"We have what is possibly becoming a failed state at our doorstep. We have criminal gangs having a heyday organising these trips in rickety boats... We need to get the Libyan factions together to form some sort of government of almost national unity."
Human smugglers are taking advantage of the political crisis in Libya to use it as a launching point for boats carrying migrants who are fleeing violence or economic hardship in Africa and the Middle East.
Up to 1,500 migrants are now feared to have drowned this year alone.
The UN High Commissioner for Refugees (UNHCR) said the latest sinking could amount to the largest loss of life during a migrant crossing to Europe.