RBS says that "due to the complexities of Williams & Glyn's customer and product mix, the programme to create a cloned banking platform continues to be very challenging and the timetable to achieve separation is uncertain".
RBS is exploring alternative means to achieve separation and divestment, but admitted that the overall financial impact on RBS is now likely to be "significantly greater than previously estimated".
Restructuring costs relating to Williams & Glyn in Q1 totalled £138 million.
In its Q1 results, RBS said that progress has been made in a number of areas necessary to becoming a standalone bank including the "resegmentation of commercial customers to an operating model fit for a challenger bank". The majority of employee roles have now been filled and over 5,000 people have been transferred onto W&G terms and conditions.
In Q1, Williams & Glyn new lending increased by 50% to £1.4 billion compared with Q1 2015. Notably, new mortgages were up 107% to £581 million, which RBS said were driven by a "more buoyant market, greater productivity and more competitive pricing".
