NY -- Standard&Poor's CreditWire 12/20/96 -- Standard&Poor's today has affirmed its double-`B'-minus foreign currency rating of Banco de Galicia Y Buenos Aires S.A., following the announcement of its planned acquisition of a 22.71% stake in Banco de Credito Nacional (BCN Barclays). Banco de Galicia will acquire 9.84 million shares at book value from the Federative Republic of Brazil, the selling shareholder, for approximately Reais (R$) 28.05 million (US$27.21 million). Such shares represent 30.29% of the total voting rights. BCN Barclays main shareholder will continue to be Barclays PLC. BCN Barclays' assets approximate R$1 billion and its equity amounted to R$123.5 million as of Aug. 31, 1996. Its headquarters are located in Sao Paulo. The acquisition of