Italy is doing its part to identify and manage migrants but many European Union countries are failing to show solidarity with frontline states, its top immigration official said on Friday.

Italy has taken in more than 320,000 migrants in the past two years and expects the overcrowded and unsafe boats to continue to arrive from North Africa this year. Coastguards rescued 359 people on Friday.

Mario Morcone, who implements immigration policy at the Interior Ministry, told Reuters Italy was struggling to implement a European Commission programme to relocate asylum seekers around the EU and relieve pressure on frontline states.

In exchange for relocation, Italy and Greece have pledged to funnel arriving migrants into "hotspots" where they are detained until they agree to be identified.

Some EU leaders have said migrants should be detained even after they have been identified to keep them from making the journey north to countries like Germany, which took in more than a million asylum seekers last year.

Austria and Slovenia this week said they would intensify border controls to keep migrants from travelling north to Germany, raising concern that Europe's biggest immigration crisis since World War Two could lead to the end of the free movement of people in the EU, one of the bloc's cornerstones.

"When it comes to hotspots and identification, Italy is absolutely doing its part," Morcone said. "No one can ask us for concentration camps because we don't build concentration camps. Nobody should think Italy and Greece alone can resolve the problems that belong to all of Europe's 28 countries."

With more than 100,000 people in its immigration centres, Italy has been able to relocate only 257 asylum seekers to other EU countries. According to the programme, up to 40,000 can be relocated over two years.

Only Syrians, Eritreans and Iraqis qualify for the programme. Syrians tend to go through Greece, but Italy has between 700-800 Eritreans who qualify, Morcone said. He also said Afghans should be allowed to be relocated.

The process "needs to be dramatically simplified. Some security controls could be done in the destination country. There needs to be more generosity by some countries," he said.

A few of the EU's 28 countries, including Sweden, have been generous, he said, but added: "Where are the other 20?"

"The Paris attacks have further complicated this situation because there's been a slowdown of destination countries that are understandably, for security reasons, late to respond to us," Morcone said.

Asked about the possibility of suspending Europe's Schengen passport-free travel zone, Morcone said: "No Schengen closure that you could imagine would be able to stand up to the suffering of the Syrian population, or Yazidis, or the suffering in Central or West Africa. The closure of Schengen would not stop them."