The AA is poised for a £1.4 billion stock market flotation that will see control of the UK's biggest roadside recovery firm pass to a group of City investors.

The business, which has four million members, is currently owned by Acromas Holdings, the private equity-backed firm behind the recent sale of shares in over-50s holidays and insurance company Saga.

Unlike the flotation of Saga, which involved retail investors, Acromas has secured the backing of City institutions such as Aviva and Invesco to buy shares worth at least £930 million as part of a management buy-in fronted by former Green Flag boss Bob Mackenzie as executive chairman.

Trading in AA shares is expected to commence later this month and value the company, which has an estimated 40 per cent market share, at £1.38bn.

Mr Mackenzie said: "We believe there are significant opportunities to grow the business."