A number of the UK's most respected fund managers have called for the removal of Prudential CEO Tidjane Thiam.
Speaking for the first time about the aborted deal, Schroders head of equities Richard Buxton says Pru management has to be accountable after it ran up huge costs in its failed AIA takeover.
"This disastrous deal has cost shareholders £450m," Buxton told The Telegraph.
"If we do not hold the management to account for this then we are giving every chief executive carte blanche to have a pop at deals without consideration for any downside risk.
"It is a charter for investment bankers to make money at the expense of shareholders."
Schroders is one of the Pru's largest investors, with a 1% stake.
While some investors believe Thiam should remain as chief executive to maintain stability, Buxton disagrees.
"Of course investors don't want to cause uncertainty at the company, but it is difficult to absolve Tidjane Thiam from responsibility," he adds.
Thiam made his first public apology since the bid's collapse on Friday. "I'm very sorry we had to spend the money and didn't get a deal," he told Bloomberg.
The costs of the failed deal almost equates to the total of Pru's last dividend.
Jupiter financials specialist Philip Gibbs agrees Thiam "must be held accountable".
"He's been out of touch with shareholders over this hugely ambitious and expensive deal. In my opinion he should go," Gibbs says.
"But the chairman should do a full assessment of all the shareholders and then make a decision, not the other way round. It's not satisfactory for a significant minority to be unhappy."
Gibbs, a long-time investor in Pru, sold his stake immediately after the insurer announced its intention to acquire AIG's Asian arm.
Pru nemesis Robin Geffen agrees with Buxton, saying it would set a bad precedent if Thiam remians in the role.
"If we don't hold somebody accountable for this, effectively we're going to get an investment bankers' charter which will enable bankers to undertake any lunatic activity for their clients safe in the knowledge they will get paid for it," Geffen told The Times.
"There's £500m reasons why somebody should be held accountable for this mess.
"In terms of who should be accountable - it's the advisers, the chief executive and the non-executives. None of them will have to pay up - that will be left to the shareholders. The decision as to what advisers are paid is made by the chief executive. In my view, he should go."
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