Fidelity International, one of the largest investors in Prudential, is calling for the resignation of chairman Harvey McGrath.
The Sunday Times reports Fidelity, which had previously called for CEO Tidjane Thiam to resign, is now seeking the departure of both, with McGrath to exit first.
McGrath and Thiam have come under fire from Pru investors over its failed $35.5bn bid for AIG's Asian arm.
The Pru has recently been in discussions with a number of shareholders angered by the firm's handling of the deal.
Fidelity owns 2.5% of Prudential according to ThomsonReuters data.
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