42 CFR 424.124 - Conditions for payment for physician services and ambulance services.
(a)Basic rules. Medicare Part B pays for physician and ambulance services if -
(1) They are furnished -
(i) To an individual who is entitled to Part B benefits; and
(2) They meet the conditions set forth in paragraphs (b) and (c) of this section.
(1) The physician services are services covered under Medicare Part B and are furnished -
(2) The physician is legally authorized to practice in the country where he or she furnishes the services.
(c)Ambulance services. The ambulance services are -
(1) Necessary because the use of other means of transportation is contraindicated by the beneficiary's condition; and
(2) Furnished by an ambulance that meets the definition in § 410.41 of this chapter.