The chain is owned and run by the Bell family

The company purchased Bells Stores - which has 54 outlets in Teesside, County Durham, Wearside and Tyneside -for what is believed to be around £20m.

The Bells Stores will continue to be run by the same management team and its head office and distribution centre will remain.

Sainsbury's said it was continuing its development in the convenience sector.

Bells Stores, which was founded in 1968 and is owned and run by the Bell family, will operate as a separate business unit.

'Successful format'

Joint managing director and vice chairman of Bells Stores, Steven Bell said: "We are delighted that we have been able to secure a deal with Sainsbury's that enables us to continue to run our business on the same strong foundations developed over the last 35 years."

Sainsbury's has 66 Local stores and a further 15 in partnership with Shell.

In June last year, it announced plans to extend the joint fuel and convenience store operation to 100 Shell locations across the UK.

It said the acquisition of Bells Stores will provide a further expansion into neighbourhood convenience retailing and, once the Shell roll-out has been completed, it will have around 220 convenience stores.

Sainsbury's group chief executive Peter Davis said: "This acquisition delivers a highly respected management team and a successful neighbourhood format, strengthening our ability to grow our presence in the convenience market."