Multiple Bank Acccouts for Vendor

Hi

In a Vendor Master we have updated Bank Details so that they would appear in DME file..

Now, we require to add 2 Banks (Bank-1 & Bank 2) for the vendor &

payment of first invoice should pickup the Bank 1 & second invoices it should pickup Bank2 in the DME

Please inform us how should I go about to cater to this requirement

Regards

Ash K