Border checks could also soon include other biometric data, such as facial and eye retina scans, as the U.S. upgrades security at its ports, airports and border crossings, said P.T. Wright, the operations director for the U.S. Department of Homeland Security's US-VISIT Program.
All people from European nations and others participating in the U.S. Visa-Waiver program would have to give additional prints, as would people traveling from nations where visas are needed, he said.
Wright, who was in Brussels to explain the new system to EU officials, said a pilot project at 10 major U.S. airports would be launched in late 2007, expanding the current program that calls for taking prints of two fingers and facial photographs.
Since the two-fingerprint scans were introduced in 2004, Wright said, security and convenience for travelers has gotten better.
"What we have encountered in the last four years is improved security as well as greater facilitation of the traveler coming to the United States," Wright said. "It's a very quick and simple scan of the fingers."
U.S. travel security restrictions have caused increased opposition in EU nations, amid demands from Brussels that Washington expand its visa-waiver program to include all 27 EU nations.
The current program allows citizens from most Western European countries and some other parts of the world to enter the country without visas, but excludes many of the newer EU member states.
EU data protection officials also have raised concerns in the past over the U.S. system and over a similar fingerprint system being set up by EU nations. They are keen to get the best privacy guarantees for citizens.