In any redevelopment plan or in the proceedings for the advance of moneys, or making of loans, or the incurring of any indebtedness (whether funded, refunded, assumed, or otherwise) by the redevelopment agency to finance or refinance, in whole or in part, the redevelopment project, the portion of taxes mentioned in subdivision (b) of Section 33670 may be irrevocably pledged for the payment of the principal of and interest on such loans, advances, or indebtedness.