Goldman Sachs yesterday suffered a rare public attack from within its ranks after a departing vice-president depicted a “toxic” culture at the Wall Street bank where executives referred to clients as “muppets”.

Greg Smith, a London-based middle-ranking banker at Goldman’s equity derivatives business, launched a scathing attack on his employer of almost 12 years, saying that he was resigning after a change in culture over the past decade that had placed clients at the bottom of the bank’s priorities.

“It makes me ill how callously people talk about ripping their clients off,” he wrote in an opinion piece for the New York Times. He said he had seen five managing directors refer to their own clients as muppets in an environment that prioritised extracting the maximum profit from them.