The application to Britain's financial regulators runs to more than 16,000 pages and contains key information on business strategy, risk and governance frameworks and financial reporting, the bank said.

RBS will launch the revived Williams & Glyn brand next year and is aiming for a flotation in the fourth quarter of 2016.

Williams & Glyn will have about 300 branches serving personal, small business and corporate customers.

RBS, 73 percent owned by the British government, has been ordered to sell the network by European competition authorities as a cost for being bailed out by the taxpayer in 2008. But the separation has been costly and beset by technology problems.

RBS said the application for a licence to the Financial Conduct Authority and the Prudential Regulation Authority "demonstrates that its systems and processes are fit for purpose and shows a clear and safe journey for customers".

(Reporting by Steve Slater; Editing by David Holmes)