The Aeon supermarket chain said Friday it will take a 15 percent stake in troubled Daiei for 46.2 billion yen, an alliance that will create the country's biggest retail group.

Under the deal, Aeon is buying the shares from its biggest stakeholder, trading house Marubeni Corp., which has 44.6 percent of Daiei's shares.

Aeon will also buy a 20 percent stake in group supermarket chain Maruetsu Inc. from Daiei for 16.5 billion yen.

Both purchases will be completed by the end of March, the companies said.

Last year, Aeon Co. obtained exclusive negotiation rights for an alliance with supermarket chain Daiei Inc., which has been trying to turn around its business after collapsing in 2004.

"By bringing together the Aeon group and Daiei group, a retail alliance surpassing 6 trillion yen in sales will be born," the companies said in a statement. That figure will put them ahead of retailer Seven & I Holdings Co., which has annual sales at about 5.5 trillion yen. Seven & I Holdings owns the Seven-Eleven convenience store chain and Ito-Yokado supermarkets.

"The groups will take up challenges that exploit our edge in size, share our business assets and expertise to speed up on reforms that will boost efficiency," the statement said.

In the deal, Aeon and Marubeni will also buy 10 billion yen worth of stocks in each other within three months, the two companies said.

The Aeon-Daiei alliance will not only create sheer size in the world's second-largest retail market, it will also garner support from a successful retail chain to turn around Daiei's troubled business.

Aeon has grown in recent years here by setting up Western-style shopping malls and offering discounts on a range of products, including electronics, clothing and food.

Aeon's drive to get a Daiei stake represents a reversal because Daiei pioneered large-scale retailing in Japan, which crushed the dominance of mom and pop shops.