An Official ICC Unpublished Opinion covers this matter.
The conclusion of this Opinion is as follows:
Conclusion/Analysis
Sub-Article 48(a) states: "A transferable Credit is a Credit under which the Beneficiary (First Beneficiary) may request the bank authorised to pay, incur a deferred payment undertaking, accept or negotiate (the "Transferring Bank"), or in the case of a freely negotiable Credit, the bank specifically authorised in the Credit as a Transferring Bank, to make the Credit available in whole or in part to one or more other Beneficiary(ies) (Second Beneficiary(ies))."
It can be seen from the above sub-Article that whilst an issuing bank can nominate a bank to transfer a credit, that transferring bank must also be a nominated bank for the handling and payment of documents. If a letter of credit is issued as being available at the issuing bank's counters (i.e. the issuing bank is also the nominated bank), the only bank that can effect the transfer is the issuing bank.
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