Westpac Banking Corp chairman Lindsay Maxsted resisted a push from a powerful group representing industry super funds for more heads to roll on the board, just hours after the resignation of chief executive Brian Hartzer, saying more departures could destabilise the bank.

After an emergency board meeting on Monday night, Mr Maxsted announced dramatic changes early on Tuesday to stem the bloodletting at Australia’s oldest bank. They included the departure of Mr Hartzer and director Ewen Crouch, who chaired the board risk committee, and bringing forward his own retirement as chairman to the first half of 2020.