Bank of Western Australia will refer customers seeking finance under an invoice discounting facility to Allianz Australia. They describe their relationship as a "strategic referral". BankWest won't transfer existing cashflow finance facilities to Allianz.The bank began its search for an alternative funder for this line of business only a month or so ago.Cashflow finance of a generic kind is a relatively new line of business for Allianz, though the firm is the largest financier of insurance premiums through Hunter Premium Funding. Allianz finances in excess of $1 billion in premiums annually through Hunter.It isn't clear how significant debtor finance is to BankWest. The bank has invested heavily in the expansion of its business and commercial banking capacity, especially in eastern Australia, as part of its effort to grow market share quickly.The Institute of Factors and Discounters estimates that lenders funded around $60 billion in business invoices under discounting or factoring arrangements in the year to March 2008. Growth in this segment was 20 per cent a year over the last two years.