Hours after the official death toll of Lampedusa shipwreck tragedy rose to 250, Brussels proposed a Mediterranean-wide search and rescue mission to intercept migrant boats.

Home Affairs Commissioner Cecilia Malmstroem presented the plan to EU ministers in Luxembourg on Tuesday.

Before putting forward her plan, Malmstroem told reporters she was going to ask ministers from the 28 member states to allow a major operation by the EU's Frontex border agency "covering the whole Mediterranean, from Cyprus to Spain".

The search and rescue operation would "help better tracking, identification and rescue of boats, especially migrants' boats", her spokesman Michele Cercone said.

"It could help prevent tragedies like the one in Lampedusa," he added.

Meanwhile, the search for bodies from the boat that sank on Thursday off Lampedusa, an Italian island between Sicily and Africa, has resumed.

Divers, who have already recovered dozens of bodies, brought up another 18 on Tuesday, bringing the total number to 250.

Many of the 500 people who were on board are still missing. The victims were mostly from Eritrea and Somalia.