Subject to the availability of appropriations, the Attorney General shall fully reimburse States and political subdivisions of States for costs incurred by such a State or subdivision for emergency ambulance services provided to any alien who
(1) is injured while crossing a land or sea border of the United States without inspection or at any time or place other than as designated by the Attorney General; and
(2) is under the custody of the State or subdivision pursuant to a transfer, request, or other action by a Federal authority.