((a)) ** No funding reduction** Nothing in this subchapter shall be construed to limit or reduce in any way the funding for any program, project, or activity serving an Indian tribe under this or other applicable Federal law. Any Indian tribe that alleges that a compact or funding agreement is in violation of this section may apply the provisions of .section 5331 of this title

((b)) ** Federal trust and treaty responsibilities** Nothing in this chapter shall be construed to diminish in any way the trust responsibility of the United States to Indian tribes and individual Indians that exists under treaties, Executive orders, or other laws and court decisions.

((c)) ** Obligations of the United States** The Indian Health Service under this chapter shall neither bill nor charge those Indians who may have the economic means to pay for services, nor require any Indian tribe to do so.