New Zealand Post is looking into alternative methods of finding funding for its subsidiary Kiwibank.Michael Cullen, chair of NZ Post, told Radio New Zealand that Standard & Poor's lowering of credit ratings for NZ Post and Kiwibank (from AA- to A+) would have some impact on the bank's growth potential.Cullen said exploring alternative options for raising capital was an extended process. "Our position is that if the government's unable to provide that then we want to discuss with them what is on the table for us finding capital elsewhere, we know that things like selling off part of the business or part of Kiwibank is off the table, but are there other forms of money-raising that might be possible," he told Radio NZ.Cullen said the company was also in the process of looking at changing New Zealand Post's deed with the New Zealand government to get more flexibility so as to make operational changes if required in the future.