TESCO, the country's largest supermarket, is planning to take over the biggest food wholesaler, Booker Group, in a £3.7 billion takeover.

But the firms' aim to create the "UK's leading food business" might attract the attention of the Competition and Markets Authority.

Cash and carry operator Booker, which operates out of Langford Mead Business Park, in Norton Fitzwarren, also owns convenience stores Premier, Budgens and Londis, which have stores in Taunton, Wellington and a number of villages in Taunton Deane and West Somerset.

Announcing the bid, Tesco chief executive Dave Lewis said: "Wherever food is prepared and eaten - 'in home' or 'out of home' - we will meet this opportunity with the widest choice and best service available."

Mr Lewis said he is confident the link up will not breach competition rules.

But Satyen Dhana, a competition partner with law firm CMS, told the BBC the CMA will look "very carefully" at the deal.

He added: "Whilst Tesco and Booker do operate in largely different segments, the CMA is likely to examine where the parties overlap and if the enhanced new business becomes a must-have trading partner for customers and suppliers.

"Tesco may not be owning any more stores, but potentially it becomes a key supplier to a large number of independent convenience stores that may compete at the local level with its own stores.

"Suppliers of goods to Tesco and Booker may also want the CMA to consider if the transaction now combines two of their largest customers."

James Lowman, chief executive of the Association of Convenience Stores, told the BBC the merger is "hugely significant".

He added: "Some retailers will welcome this news, others will be concerned about competing with stores supplied through the merged Booker and Tesco business, and some will be uneasy at the prospect of working in partnership with one of their biggest historical competitors."

Under the terms of the cash and shares offer, which saw Tesco shares rise this morning, Booker shareholders will own about 16 per cent of the combined group.