Credit card super brand, American Express, would not comment on the speculation on Monday it was in discussions with a global institution to sell its private banking business. The Amex private banking business increased its assets 11 per cent to $22.5 billion in 2006 according to the group’s annual report last year. But the report noted a tough interest rate environment continued to put pressure on margins. The Amex Private Bank reported a reduction in the return on segment capital from 23.2 per cent for 2005, to 20.9 for 2006. A Reuters story quoted an unnamed source close to the business saying the sale of American Express Private Bank is likely to happen within the next few weeks. The private banking unit provides investment services, deposit accounts, treasury services, loans, fiduciary services and insurance to high net worth individuals in Europe, Asia, Latin America, the US and Canada. There has been no mention of any planned sale of the private banking business in investor communications to date.