Deutsche Bank’s incoming co-chief executive John Cryan on Wednesday postponed a detailed presentation of the giant German lender’s new strategy until the end of October but said he remains committed to trimming operations.

In a letter to staff posted on the bank's website, he said: "I am not going to tell you that all will be sweetness and light in the coming months," setting the stage for potentially deep cuts among staff and an increased focus on changing the business's corporate culture.