As many as 1,750 staff at Credit Suisse First Boston are to lose their jobs as John Mack, chief executive, takes the tally of job losses at the firm since his arrival to more than 6,500.

In an internal memo to staff, Mack, known on Wall Street as "Mack the Knife", said CSFB had no choice but to cut more staff given the further decline in market conditions. He has already cut costs by $1.8bn (€1.9bn) by making 4,800 staff redundant since his arrival, and is now aiming to reduce headcount by a further 5% to 7%.