All passengers entering the United States by air will be required to show passports from January 23 2007, including US nationals and all travellers from Canada, Mexico and other countries.

The deadline was revealed in an interview with Homeland Security Secretary Michael Chertoff in an interview with The Associated Press.
The interview was the first indication of an absolute cut off date for air passengers, although passengers entering the US across land borders or by sea still have until June 1 2009 before they will also require passports.
People from Canada, Bermuda and Mexico who enter the United States frequently have either used special border-crossing cards in the past, or have been allowed to use other forms of identification, including driver's licenses.