The Secretary of the Interior is authorized, in his discretion, to acquire, through purchase, relinquishment, gift, exchange, or assignment, any interest in lands, water rights, or surface rights to lands, within or without existing reservations, including trust or otherwise restricted allotments, whether the allottee be living or deceased, for the purpose of providing land for Indians.
For the acquisition of such lands, interests in lands, water rights, and surface rights, and for expenses incident to such acquisition, there is authorized to be appropriated, out of any funds in the Treasury not otherwise appropriated, a sum not to exceed $2,000,000 in any one fiscal year: Provided, That no part of such funds shall be used to acquire additional land outside of the exterior boundaries of Navajo Indian Reservation for the Navajo Indians in Arizona, nor in New Mexico, in the event that legislation to define the exterior boundaries of the Navajo Indian Reservation in New Mexico, and for other purposes, or similar legislation, becomes law.
The unexpended balances of any appropriations made pursuant to this section shall remain available until expended.
Title to any lands or rights acquired pursuant to this Act or the Act of July 28, 1955 (69 Stat. 392), as amended (25 U.S.C. 608 et seq.)  shall be taken in the name of the United States in trust for the Indian tribe or individual Indian for which the land is acquired, and such lands or rights shall be exempt from State and local taxation.