TESCO’S Liverpool born chief executive Sir Terry Leahy retires today after 14 years at the helm as the supermarket is launching a £200m price war with rival Asda.

Tesco’s move to up the ante against resurgent competitor Asda comes on the same day that Sir Terry Leahy celebrates his last day in charge – and his 55th birthday.

Sir Terry – hailed as one of Britain’s great retailers – will hand over to successor and fellow Liverpudlian Philip Clarke on Tuesday after transforming the supermarket from the UK’s number two chain to the clear market leader and an international force.

A former pupil of The Blue Coat School, Mr Clarke takes over amid a mounting price battle with Asda, which has been leading a sales growth revival with its Asda Price Guarantee – relaunched in January pledging to sell groceries at least 10% cheaper than its major rivals.

Tesco is lowering prices on more than 1,000 items from today and promising to pay shoppers “double the difference” on products found cheaper at Wal-Mart owned Asda.

Asda last week revealed a robust Christmas trading performance that left rival Tesco in the shade, reporting like-for-like sales up by 2.6% including VAT in the final quarter of 2010 against Tesco’s sales rise of 0.6% for its six-week festive period.