Swiss labour inspectors said Thursday they were investigating the Zurich offices of US bank Goldman Sachs after staff complained about breaches of rules on working hours.

The issue of bankers' often-lengthy working hours has hit the headlines following the death of a trainee at the London offices of Bank of America Merrill Lynch, which has launched an internal audit.

Irene Tschopp, spokeswoman for Zurich's cantonal (state) labour inspectorate, told AFP that a team visited the Goldman Sachs offices Wednesday.

"I can confirm that we received a complaint concerning working hours," she added.

She declined to give further details, citing data protection rules.

The Swiss daily Tages-Anzeiger reported that the Goldman Sachs staff association in Zurich filed the complaint 10 days ago.

It said that the association alleges the bank has failed properly to log working hours and make payments for overtime.