Investment banks could start another round of European lay-offs in the coming months as they struggle with a deal slowdown and placid markets, industry watchers said.

At least one firm is already taking action to trim costs. A memo was sent to staff in Credit Suisse's investment banking and capital markets division in the first days of September about a consultation period on potential job cuts, according to people who have read it. The number of bankers likely to be affected is undecided and two people at Credit Suisse familiar with the plans talked of "pruning" rather than large-scale lay-offs.