Credit Suisse is expanding its US wealth management business while avoiding trying to buy or build a large broker-dealer operation, the Zurich-listed bank has said, according to Reuters.

The Swiss bank's US advisory force of 407 relationship managers in 15 offices is small compared with a powerhouse like Morgan Stanley Smith Barney, which ended last year with 18,135 advisors and 895 offices worldwide, the report said.

The bank has emerged from the financial crisis relatively unscathed compared with its Swiss rival, UBS, although it has not been immune to the crisis.

Yet Credit Suisse says its focus on serving only the very rich - individuals with assets totalling at least $10 million - and has created a profitable business that recent events show may also be more sustainable.

"The reason we haven't tried to buy a broker-dealer, or replicate a big broker-dealer, is we think it's a dying business model," Credit Suisse Private Banking Americas chief executive Anthony DeChellis told the news agency. "It won't be gone tomorrow, but it's a model that is significantly challenged."

"For the past three years, in the midst of the worst environment in decades, we doubled the size of our business," Mr DeChellis was quoted as saying. "We've been able to take advantage of some of the dislocation,” he said.

Credit Suisse has "aggressive growth plans" this year, Paul Simons, co-head of Credit Suisse's US private bank, said in a separate interview, the agency said.

The bank added 50 advisors in 2007, 120 during turbulent 2008, and roughly 50 last year - more than doubling its advisory force over three years.

"Last year we grew when there weren't a lot of wealth managers that did," said Mr Simons, adding that he expects to continue recruiting advisors this year.

Mr DeChellis said that over time he would like to have 700 advisors in the US, a 75 per cent increase, and bring the number of offices up to 18 or 20.