The U.S. version of the biometric passport (which is also referred to as an "Electronic Passport") will only have digital imaging placed onto the contactless chip, as opposed to the European version. However, the chip used in the U.S. passport will be large enough (64 kilobytes) to allow it to contain additional biometric identifiers should the need arise in the future. The U.S. Department of State began issuing biometric passports to government officials and diplomats in early 2006. It began issuing regular biometic passports at its Colorado Passport Agency on August 14, 2006; though they still expect that nearly all new or renewed passports issued by the department to American citizens will be biometric by the end of 2006, other sources say it won't happen until mid-2007.
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