Tesco is to buy wholesaler Booker for £3.7bn, in a deal it claims will create "the UK's leading food business".

The deal has stunned the grocery sector, but was welcomed by investors in both Tesco and Booker, sending their shares higher.

What does the tie-up mean and how will affect the shopper on the high street?

What is Booker?

Booker is a cash-and-carry wholesaler that supplies food to 120,000 independent retailers nationwide. It has 172 depots, plus 30 under the Makro brand, where small business owners can buy goods in bulk.

It also owns the Londis, Budgens and Premier brands, which operate on a franchise basis. This means the shops are independently owned by small business people, who pay Booker for the branding, access to certain products and deals, as well as IT and logistical support. Being part of a buying group keeps costs down for independent retailers.