LONDON (Reuters) - Shares in Nomura and Credit Suisse fell further on Wednesday, with a collective $9 billion wiped off their market value so far this week as the banks braced for big losses from the blow-up of U.S.-based hedge fund Archegos Capital. Credit Suisse and Nomura were slower than rivals to cut their exposure to Archegos, a family office run by former Tiger Asia manager Bill Hwang. Global lenders that acted as brokers for Archegos may have to write down more $6 billion after the fund defaulted on payments, Reuters has reported.