Royal Bank of Scotland could split Coutts International into European and Asian divisions to attract Far East buyers put off by the crackdown on tax evasion in Europe.

RBS is selling the international arm of its private bank to raise up to £1 billion, but believes potential bidders in Singapore and Japan may be reluctant to take on exposure to European clients who could face tax investigations.

Banks in Switzerland, where Coutts International is based, have been grappling with a US tax-evasion probe. The bank manages £24bn and made a £68m profit last year. Around 40 per cent of clients are in Asia with the rest in Europe and the Middle East.