Sumitomo Mitsui Financial Group Inc. said Wednesday it will buy at least 2 percent of South Korea's KB Financial Group Inc.

The sale of about 7.1 million shares will be made in as many as four parcels between November and June 2009, Seoul-based KB Financial, which controls South Korea's largest lender, said in a regulatory filing. The price will depend on market conditions, the South Korean firm said.

Sumitomo Mitsui and its bigger rivals Mitsubishi UFJ Financial Group Inc. and Mizuho Financial Group Inc. are taking advantage of falling stocks and a stronger yen to buy stakes in foreign financial firms.