Tesco, the world's No. 3 retailer, said last week it was investing £150m in a relaunch of its Clubcard loyalty scheme in the UK.

It said the investment is expected to attract at least one million more customers. In a statement, Tesco said that prior to the relaunch customers could spend Clubcard vouchers at face value across the store and on-line or increase the value by up to four times by trading them for a range of deals with the retailer's partners such as restaurants and theme parks. However, from today customers can receive double the value of Clubcard vouchers in Tesco stores and on-line when they buy products including clothing, baby goods, wine and mobile phone airtime.

The retailer said the change to the scheme was the biggest since it launched in 1995. Shares in Tesco, which have lost 20 per cent of their value over the last year, closed on Thursday at 345 pence, valuing the business at £27.3 billion.