TEXT: Undated file photos of an ASDA and a Sainsbury's sign. Britain's competition watchdog has launched the second stage of its investigation into the proposed £12 billion merger between the supermarkets. PRESS ASSOCIATION Photo. Issue date: Wednesday September 19, 2018. The deal will now be subject to a so-called Phase Two in-depth probe to assess how it could affect competition for UK shoppers, the Competition and Markets Authority (CMA) confirmed. See PA story CITY Sainsbury. Photo credit should read: Yui Mok/PA Wire