Tea company Ringtons is brewing up plans to diversify its traditional door-to-door delivery business by opening a chain of up to 100 tea and coffee shops across the UK.

The famous Newcastle company plans to take on Whittards of Chelsea after recruiting the tea and coffee chain's chief executive Mark Naughton-Rumbo and two senior executives in April this year.

Family-owned Ringtons, which employs more than 500 staff and celebrates its 100th anniversary next June, wants to add at least 50% to its current annual turnover of around £30m with the expansion over the next 10 years.

Director Simon Smith said: "We had been looking at opportunities for growth and had a latent desire to go into retail for some time but lacked the expertise to tackle what needs to be a substantial investment."

The first store, which will operate under the Ringtons name, will open in Cambridge later this month, and will be followed by stores in Canterbury and Brighton before the end of the year. The company is currently scouting for a fourth store to be opened some time next year.

The stores, which will be up to 500sqft in size in "secondary" high street locations, will initially stock 200 varieties of tea and coffee, rising eventually to 500, as well as teapots, china, biscuits and connected products.

Around 80% of the company's current turnover is generated from home deliveries to nearly 300,000 customers in the North and Midlands, with the rest from contracts to supply tea to Marks & Spencer and Waitrose. Mr Smith said the company's "ultimate" aim is to rival Whittards, the UK's largest tea and coffee vendor with 120 outlets, which was taken over by Icelandic investor Baugur in December last year.

He said: "The biggest point of difference is the brand values that we have built up over a long period and which we will bring to the high street in terms of quality and service.

"We will also buy, blend and package more than 95% of the teas and coffees that we will supply to the new stores.

"Controlling the supply chain is essential for the business to be able to keep up the flow of innovation and keeping exciting products flowing to customers.The relationship with our suppliers, whose tea estates we visit once a year, is important in maintaining quality and in the interests of an ethically-based relationship."

The expansion of the company, which was founded in 1907 by Mr Smith's great-great grandfather Sam Smith and William Titterington, would be largely funded without resorting to outside equity.

Mr Smith said: "As a family we believe that we can significantly increase the scale of the business and maintain the firm's values without giving up control, but at the same time as partnering up with people who have the specific knowledge of the market that we are going into."

While the stores would initially be rolled out in the south of England, the company would look to establish stores in the North-East in later expansion phases. Mr Smith said: "The stores will stock a greater variety of teas.

"The home delivery market has much narrower tastes which would give us scope to roll out the stores in the North-East, where the Ringtons is an established name, further down the track."