Royal Bank of Scotland (RBS) has revealed that it may miss the EU deadline to offload Williams & Glyn arm by the end of 2017.
The state-backed lender said in a statement that the timetable to achieve the proposed separation is uncertain and that it is exploring alternative means to divest the unit.
"Due to the complexities of Williams & Glyn’s customer and product mix, the program to create a cloned banking platform continues to be very challenging," RBS said in the statement.
According to RBS, the overall financial impact of the disposal is expected to be bigger than what was previously estimated.
Williams & Glyn was due to be divested by the end of 2017, as a condition of the £45bn government bailout that scandal-hit RBS received during the financial crisis.
Ahead of the sale, the lender has decided to shed its RBS branding from more than 500 high street branches in England, Wales and Scotland.

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By GlobalDataOver 300 branches in England and Wales will be rebranded as Williams & Glyn, whereas about 200 branches in Scotland will be renamed to Royal Bank of Scotland.