Cryan said that it was important for the bank to embrace a "revolutionary spirit" and warned that this would mean an end to an era where accountants acted like abacuses.

"We have to find new ways of employing people and maybe people need to find new ways of spending their time,” he said in comments reported by the Financial Times.

Cryan did not elaborate on how many of the bank's 100,000 staff may lose their jobs to a robotic rival, other than to say it would be "a big number".

And he hinted that those accountants acting like abacuses were most at risk. "The truthful answer is we won’t need as many people…In our banks we have people behaving like robots doing mechanical things, tomorrow we’re going to have robots behaving like people."

Cryan's comments come in the middle of a long-running cost-cutting exercise at the bank. In addiiton to overhauling its IT structure, the bank has also announced a number of job cuts and branch closures.

Although, on a more positive note, the Deutsche Bank chief executive did add that the use of new technology and robots would not always be a direct replacement for human staff.

Instead some staff would be "upskilled" and given more interesting work as the more commoditised tasks were entrusted to automation and robots.

Cryan is not the only figure to warn about the possible impact of robotics and artificial intelligence on employment in the banking sector. A 2016 report from the World Economic Forum predicted that auotmation would result in the loss of 5 million jobs by 2020.