Moody's on Dec. 19 assigned ratings to Banco Santander SA units Abbey National Treasury Services PLC and Santander UK Group Holdings PLC.

The agency assigned to U.K.-based Abbey National Treasury Services long-term issuer ratings of Aa3, with a stable outlook, and short-term issuer ratings of P-1; and to both Abbey National Treasury Services and Santander UK Group a baseline credit assessment and adjusted baseline credit assessment of "a3."

Moody's also affirmed Abbey National Treasury Services' Aa2(cr)/P-1(cr) long- and short-term counterparty risk assessment; Aa2/P-1 long- and short-term counterparty risk ratings; P-1 short-term bank deposits; and Aa3 long-term bank deposits, with a stable outlook.

The baseline credit assessment of Santander UK Group is aligned with the baseline credit assessment of Santander UK, and reflects the predominance of Santander UK within the U.K. sub-group.

The baseline credit assessment of Abbey National Treasury Services follows the ring-fencing scheme undertaken by Santander UK Group for compliance with the U.K. ring-fencing provisions, and is driven by its expected high degree of integration with the rest of the U.K. sub-group.

The long-term ratings, along with the outlooks, of Abbey National Treasury Services are also aligned with those of Santander UK.