UK supermarket chain Sainsbury said it was in talks to merge with rival Asda in a deal that would create a retail giant with around 30 percent of the UK market.
"Sainsbury's confirms that it and Walmart Inc. are in advanced discussions about a combination of the businesses of Sainsbury and Asda," Sainsbury said in a statement.
Britain's largest retail chain is currently Tesco with a market share of 27.6 percent, followed by Sainsbury and Asda with 1
The combined company would have 2800 stores.
Sainsbury said another explanation about the proposed merger would be made at 0600 GMT on Monday.
The Press Association reported that the business would have a value of £ 10 billion (€ 11.4 billion, $ 13.8 billion).
Richard Lim of the Economic Research Advisory Retail Economics told the BBC that the merger is a "On the UK food market, which has reached epic proportions, the market has fundamentally changed."
"The potential link would make Tesco a common one Doing business, "he said.
Joanne McGuinness, Usda National Officer "We will seek urgent discussions with companies to find out in more detail what a possible merger will entail."
"Our priorities will be to protect our members and ensure that there is no trade between retailers over their jobs or income."
Tim Roache, Secretary-General of the GMB union, said: "Our top priority is it to secure the work of each Asda member both in the shops and in distribution.
"We are calling for an urgent meeting with Asda to receive the answers and assurances our members need and deserve. GMB will ensure that the voices of supermarket workers are not lost in all M & A talks.
UK retail sales have been hit hard in recent months by a combination of slower consumer spending, slower economic growth and snowy weather
Traditional retailers such as Sainsbury and Asda were also undermined by the growth of online retailers and low-cost rivals such as Aldi and Lidl Pressured.
Sainsbury previously bought the catalog trader Argos and the furniture retailer Habitat in 2016.  The transaction should still be approved by the UK's Competition and Market Authority (CMA).
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