Notwithstanding any other provision of law, but subject to paragraph (2), payments to which a facility of the Service is entitled by reason of a provision of title XVIII or XIX of the Social Security Act [42 U.S.C. 1395 et seq., 1396 et seq.] shall be placed in a special fund to be held by the Secretary. In making payments from such fund, the Secretary shall ensure that each Service unit of the Service receives 100 percent of the amount to which the facilities of the Service, for which such Service unit makes collections, are entitled by reason of a provision of either such title.

Amounts received by a facility of the Service under subparagraph (A) by reason of a provision of title XVIII or XIX of the Social Security Act shall first be used (to such extent or in such amounts as are provided in appropriation Acts) for the purpose of making any improvements in the programs of the Service operated by or through such facility which may be necessary to achieve or maintain compliance with the applicable conditions and requirements of such respective title. Any amounts so received that are in excess of the amount necessary to achieve or maintain such conditions and requirements shall, subject to consultation with the Indian tribes being served by the Service unit, be used for reducing the health resource deficiencies (as determined in section 1621(c) of this title) of such Indian tribes, including the provision of services pursuant to section 1621d of this title.

Each tribal health program making the election described in paragraph (1) with respect to a program under a title of the Social Security Act [42 U.S.C. 301 et seq.] shall be reimbursed directly by that program for items and services furnished without regard to subsection (c)(1), except that all amounts so reimbursed shall be used by the tribal health program for the purpose of making any improvements in facilities of the tribal health program that may be necessary to achieve or maintain compliance with the conditions and requirements applicable generally to such items and services under the program under such title and to provide additional health care services, improvements in health care facilities and tribal health programs, any health care-related purpose (including coverage for a service or service within a contract health service delivery area or any portion of a contract health service delivery area that would otherwise be provided as a contract health service), or otherwise to achieve the objectives provided in section 1602 of this title.

The amounts paid to a tribal health program making the election described in paragraph (1) with respect to a program under title XVIII, XIX, or XXI of the Social Security Act shall be subject to all auditing requirements applicable to the program under such title, as well as all auditing requirements applicable to programs administered by an Indian health program. Nothing in the preceding sentence shall be construed as limiting the application of auditing requirements applicable to amounts paid under title XVIII, XIX, or XXI of the Social Security Act.

Any tribal health program that receives reimbursements or payments under title XVIII, XIX, or XXI of the Social Security Act shall provide to the Service a list of each provider enrollment number (or other identifier) under which such program receives such reimbursements or payments.

The Secretary, acting through the Service and with the assistance of the Administrator of the Centers for Medicare & Medicaid Services, shall examine on an ongoing basis and implement any administrative changes that may be necessary to facilitate direct billing and reimbursement under the program established under this subsection, including any agreements with States that may be necessary to provide for direct billing under a program under title XIX or XXI of the Social Security Act [42 U.S.C. 1396 et seq., 1397aa et seq.].

The Service shall provide the Administrator of the Centers for Medicare & Medicaid Services with copies of the lists submitted to the Service under paragraph (2)(C), enrollment data regarding patients served by the Service (and by tribal health programs, to the extent such data is available to the Service), and such other information as the Administrator may require for purposes of administering title XVIII, XIX, or XXI of the Social Security Act.