Two Muslim sisters have accused a broking firm of religious discrimination after they were allegedly banned from working with Jewish clients.
Their claim is one of more than 200 due to be heard at an employment tribunal against City of London firm Tradition Securities and Futures.
One of the women said a bank client was allocated to her Jewish co-worker because they "had in common both language and race".
Tradition rejects all allegations in the case, which opened on Wednesday at London Central Employment Tribunal and is scheduled to last 55 days, making it one of the longest in British legal history.
Both women are of French-Moroccan descent and in their early thirties. They quit Tradition in 2006, two years after moving from the company's Paris office.