The longest serving major bank chief executive, ANZ’s Shayne Elliott, will announce his retirement this week with the lender expected to appoint an outsider to oversee the integration of its $4.9 billion Suncorp purchase.

Mr Elliott’s resignation means three of the country’s four major banks will have appointed new chief executives this year. National Australia Bank appointed Andrew Irvine to succeed Ross McEwan in February and Anthony Miller becomes Westpac’s chief executive next week.