Former Sun editor Kelvin MacKenzie has launched a social media service to help consumers name and shame companies that fail to respond to complaints.

The platform, called A Spokesman Said, lets consumers sign up and publish complaints about companies that mistreat them.

Once the complaint is approved and published, a virtual countdown clock starts ticking to measure the time it takes for the company to respond. Companies have two days to respond.

They are then ranked and penalised according to a “Customer Powerscore”, based on their response speed and whether the complainant is satisfied with their response.

Users of the site have to sign up using their real identities, and are encouraged to upload evidence such as pictures and Youtube links to support their complaints.

MacKenzie said: “As an editor I know the power of publicity to force companies and politicians to do the right thing.

“Now we are putting that power directly into the hands of the man or woman in the street.

“This is something I have been thinking about for over thirty years. Thanks to social media and web technology we can now really make it work on a big scale.”

MacKenzie’s new venture coincides with his return to The Sun as a columnist. He is best known for editing The Sun from 1981 to 1994.

Since leaving The Sun MacKenzie has written for the Telegraph and the Daily Mail, and has invested in private media ventures.

He sold the video rights company Base 39, which he founded with his son Ashley, for £50m last year.

A Spokesman Said is funded personally by Kelvin MacKenzie and a group of private backers. City AM have reported that Rupert Murdoch is among those backing him.