The United States soon plans to give the world police body Interpol information on about 400,000 lost or stolen US passports to stop "terrorists" and others from using them.
"We are working toward sharing lost and stolen passport information with Interpol," said one US official, adding that Washington was close to releasing passport numbers for the travel documents.
"It's anti-terrorism. It's about protecting the homeland," said a second US official.
The 400,000 passports involved were each issued to someone who later reported them lost or stolen, rather than blank US passports, which officials say seldom go missing.
The United States has tightened border security since the September 11th, 2001, attacks, requiring millions of foreigners to be fingerprinted on arrival at US airports.
Interpol Secretary-General Ronald Noble said last week most countries fail to supply the Lyon, France-based body with details of stolen passports, suggesting this was a major loophole that had to be plugged to help prevent attacks.
Mr Noble said Interpol's database contained serial numbers of 1.1 million stolen travel documents of which 188,609 were blank papers in which criminals or militants can insert photographs, descriptions and aliases, therefore posing a special risk.
Despite the large number of entries, Mr Noble said only 39 of Interpol's 181 member states were contributing information on stolen documents and only 47 had so far accessed it, a situation for which he said "there is no acceptable excuse".
The system enables police and immigration officials to check whether a travel document is stolen simply by typing its number into a computer. The process takes only seconds via I-24/7, a new, encrypted Internet-based network that Interpol has so far rolled out to 96 countries.