Japan’s biggest bank sees value in further share buybacks as its $7.5 billion deal to sell a U.S. regional lender adds to a growing cash pile.

"We are always looking for growth investment opportunities,” Hironori Kamezawa, chief executive officer of Mitsubishi UFJ Financial Group, said in an interview on Dec. 16, adding that the lender will consider acquisitions in Asia and the United States. "Unfortunately, buying our own shares is a very good investment, because they are cheap.”

Kamezawa’s comments underscore the challenges facing Japan’s biggest banks as they weigh how to invest billions of dollars in profits amid ultralow interest rates and tepid loan demand at home. MUFG has said it will spend around half of its expected ¥2 trillion ($15.2 billion) or more in net income over two years on buybacks or investing for growth. That number includes additional capital created by the sale of MUFG Union Bank to U.S. Bancorp, which closed earlier this month.