Michael Barnett is to stand down as the chief executive of the Auckland Chamber of Commerce and will be replaced by former National Party leader Simon Bridges.

Auckland Chamber chairwoman Charlotte Parkhill confirmed an earlier NZ Herald report that Barnett would step down from the role in August but would remain involved in the organisation, driving key projects including Firststeps, a mental health initiative with government focused on business, the Regional Business Program, the NZ Chamber network, and his role with the International Chamber.

Barnett was appointed CEO of the Auckland Chamber in 1991 after several years in an international role.

At that time, the chamber had a small staff and membership that reflected larger businesses.

Under his leadership the chamber has grown significantly and has built a special relationship with small and medium business and provided them with a credible voice to Government.

Barnett has worked closely with ministers and all political parties over three decades, which has enabled business to be heard and supported.

He has provided leadership within the chamber network both nationally and internationally and developed key business partnerships and networks that have been good for business in Auckland and NZ.

Parkhill said: "The contribution that Michael has made to the business sector in Auckland and New Zealand over the last 30 years has been enormous. He has been instrumental in promoting business interests and securing support for the sector from a financial, resourcing and mental health perspective.

"The chamber board has been consistently impressed with the voice that Michael has given to business and his entrepreneurial approach to issues faced by the sector. We are very pleased that Michael will be remaining with the chamber in his new role".

Parkhill also confirmed that Simon Bridges, former National Party leader and Member of Parliament, would take the chamber CEO role and that details of his appointment would be released soon.

In the meantime, she asked that the business and public sectors take time to recognise Barnett's huge contribution to Auckland and NZ while in the CEO role.