Draft proposals for the meeting include offering 5,000 places for resettlement for migrants "qualifying for protection" under a pilot project.
More than 800 people drowned off Libya's coast on Sunday, bringing the number of deaths this year to 1,750.
More than 21,000 people are estimated to have reached Italy this year.
Italian PM Matteo Renzi has called for direct action against people smugglers.
He described them as "the slave traders of the 21st Century".
A draft statement for Thursday's meeting in Brussels says leaders will commit to "undertake systematic efforts to identify, capture and destroy vessels before they are used by traffickers".
It says EU foreign policy chief Federica Mogherini "is invited to immediately begin preparations for a possible security and defence policy operation to this effect, in accordance with international law".
