Troubled Swiss banking giant UBS AG (NYSE: UBS) said it will cut 2,000 investment banking jobs over the next five years as it embarks on a course to focus on its core wealth management business.

UBS shares are down about 1.3 percent in early afternoon trading in New York.

The job cull would slash the number of bankers to 16,000.

The bank said it plans to reduce the size of its risky assets by half, or 145 billion Swiss francs ($158 billion).

"We have chosen to substantially reduce the risk profile of the bank by exiting and downsizing businesses which are not value added to our client franchise or deliver unattractive risk-adjusted returns," new chief executive Sergio Ermotti said in a statement.

Three months ago, the bank said it would cut 3,500 jobs, or 5 percent of its total workforce, in an effort to save the company 2 billion Swiss Francs ($2.2 billion) annually.

UBS also reduced its return-on-equity target to 12-17 percent from the previous 15-20 percent range, in recognition of stricter capital rules faced by European banks.

Ermotti took over the bank’s helm after Oswald Gruebel was forced to resign in September in the wake of trading scandal by a rogue London employee who cost the company $2.3 billion.

 Separately, UBS said that Axel Weber, the former president of the Bundesbank, Germany’s central bank, will succeed Kaspar Villiger as board chairman in May 2012.