Dave Lewis insisted the long-term benefits to Tesco’s customers will outweigh the short-term effect on shareholders as he announced another profit warning as he revealed nearly a thousand staff have been retrained to prevent a repeat of its £263 million accounting fiasco. Lewis predicted profits for the country’s biggest supermarket could be just £15 million in the UK in the second half of the year. Full-year profits will now be no more than £1.4 billion, a fall of 57 per cent on last year, with UK profits expected to be down by a staggering 96 per cent.