Britain’s biggest retailer Tesco has launched its most aggressive Christmas discount drive, designed to blow its upmarket rivals out of the water.<br /><br />The supermarket giant is slashing the prices of more than 200 products in its Finest range in a bid to stop shoppers defecting to Waitrose and Marks & Spencer for luxury food treats. Offers include halving the price of a lobster thermidor to £10 and slashing the price of puddings. The promotions will be backed by a high-profile TV campaign.<br /><br />The savage assault on the high street is part of the retailer’s efforts to cling on to customers. The group saw its first market share growth in almost two years in the 12 weeks to 1 November, according to the latest TNS Worldpanel figures, after it re-launched its loyalty Clubcard with double points. <br /><br />Last week it also made an unprecedented move to bring forward February’s release of money-off coupons for clubcard holders – amounting to a potential saving of £67m. Analysts expect a three per cent hike in like-for-like sales as the revival of price-war tactics seems to be working for Tesco.