Former prime minister Sir John Key is retiring as the chair of ANZ New Zealand.

The bank said Sir John would also retire as a director of its Australian parent, ANZ Group, effective from the middle of next month.

He was appointed chair of ANZ New Zealand in January 2018 and joined the group board the following month.

Sir John was New Zealand’s prime minister between 2008 and 2016.

ANZ has appointed Scott St John as the new chair of its New Zealand division, to succeed Sir John.

St John is the chair of Mercury Energy and Fisher and Paykel Healthcare

Sir John said he was “proud” to have helped make ANZ “a better company”.

“While it’s the right time for me to step back on my commitments, I know ANZ is in a strong position and that Scott St John will be an outstanding chair of ANZ New Zealand and director of ANZ Group.”

ANZ Group chair Paul O’Sullivan said Sir John’s “unparalleled” business and political experience played a “critical role” in the bank’s success.

“As a board we will miss his wise counsel, global insights and good humour and we wish him and his family the very best for the future.”