The Welsh Government plans to raise concerns about the impact on farmers of the proposed merger between the Asda and Sainsbury supermarket chains with the Competition Commission.
A cabinet minister made the commitment after Plaid Cymru AM Simon Thomas said Welsh farmers face being squeezed by what he called "anti-competitive market forces".
Simon Thomas added that the powers of the Supermarket Ombudsman, who deals with complaints that suppliers are being treated unfairly, need to be be beefed up considerably.
In response, the Leader of the House, Julie James, said ministers will be raising their concerns with the inquiry that the Competition Commission is expected to carry out before deciding if the merger can go ahead.
Details of the deal came after the companies – the UK’s number two and three supermarkets – confirmed on Monday morning that the deal will create a retail titan with a bigger share of the market than Tesco.
It would have combined revenues of £51 billion and boast a network of 2,800 Sainsbury’s, Asda and Argos stores.
It will see Asda owner Walmart hold 42% of the new business and receive £2.97 billion in cash, valuing Asda at £7.3 billion.