U.K. grocer J Sainsbury PLC plans to buy Walmart Inc.'s Asda in a £7.3 billion ($10 billion) deal that would transform the country's supermarket industry and leave the U.S. retailer as the combined company's biggest shareholder.

Sainsbury will pay Walmart £2.98 billion in cash and £4.3 billion in stock, the U.K. company said in a statement Monday detailing the terms after confirming a Bloomberg News report on the plan over the weekend. Walmart would get a 42 percent stake in the merged entity, Sainsbury said.

Sainsbury shares rose as much as 21 percent in London. Tesco PLC, the current U.K. grocery market leader, fell as much as 3.4 percent, while Wm Morrison Supermarkets PLC dropped as much as 4.4 percent in early trading.