When any redevelopment authority, which is created to operate within any city or county, becomes authorized to transact business and exercise its powers, the city council or the county commissioners, as the case may be, may make such appropriations to an authority out of any moneys in such city or county treasury not appropriated to some other purposes as is deemed necessary to assist an authority in carrying out its public purposes. Any State public body located in whole or in part within the field of operation of a redevelopment authority shall have the power from time to time to lend or donate money to the authority. Said State public body may issue general obligation bonds for the purpose of obtaining funds for local contributions required by any Federal law pertaining to redevelopment.