GENEVA (Reuters) - Finger-printing and registering all refugees reaching Europe would keep out Islamist militants bent on attacks, the European Commission’s deputy chief said on Monday in response to concerns raised in some EU countries.

Frans Timmermans, First Vice-President of the European Union addresses a plenary meeting of the United Nations Sustainable Development Summit 2015 at the United Nations headquarters in Manhattan, New York September 27, 2015. REUTERS/Mike Segar

The top U.N. refugee official said any militant would be more likely to fly into Europe on a false passport than pay thousands to people smugglers to risk a dangerous sea journey to the continent and then discovery through finger-printing.

European Commission Vice President Frans Timmermans said the European Union could better handle a record influx of refugees and migrants by improving protection of its external borders and ensuring people not entitled to asylum are sent back.

Timmermans, asked about how to ensure militants do not enter the refugee flow and pose threats to the EU, a concern raised by immigration-wary authorities in some member states, told a news briefing: “Simply by finger-printing people on arrival.

“If done properly you can filter out the terrorists. What I don’t like is that some people use this argument against all refugees from everywhere, (saying), ‘But terrorists will arrive among them’,” he said.

“That is the lamest excuse that is being used for not taking your international responsibility,” Timmermans added. “If we do our jobs and we make sure as soon as people arrive they are finger-printed and identified, then that problem doesn’t exist.”

Timmermans added however that he did not believe militants would join the refugee stream if they knew they would be fingerprinted on arrival. Better protecting the EU’s external frontiers was ultimately the best security step, he said in earlier remarks to the UNHCR’s executive committee.

But Antonio Guterres, the U.N. High Commissioner for Refugees, told reporters that militants probably knew better than to try to enter the EU on a perilous voyage across the Mediterranean to carry out any attack plan.

“A terrorist would be very stupid if instead of coming with a well-prepared false passport (and) taking a plane into Europe through a legal channel, he would have to pay thousands of dollars to smugglers for a boat that can sink, and come into a reception center where he would be finger-printed, and then to start walking through different borders..., to get finally where they (want to be),” Guterres said.

German Chancellor Angela Merkel said at the weekend that Europe needed to protect its external frontiers as it faces the greatest influx of refugees since World War Two - a crisis that she said was “testing Europe’s mettle”.