TOKYO, March 2 (Reuters) - Nippon Life Insurance Co said on Friday it had agreed to buy an 85.1 percent stake in the domestic unit of U.S.-based MassMutual Financial Group for about 104.2 billion yen ($980 million) as it aims to boost its bancassurance sales.
Japan's biggest private-sector life insurer plans to pay for the stake with cash on hand and expects the deal to be completed in May or June pending regulatory approval, it said in a statement.
The deal had been expected after reports last year that the companies were in talks.
Japanese insurers have been hit by diminishing returns from investments in Japanese government bonds and other securities amid the Bank of Japan's massive stimulus measures, prompting them to seek riskier but higher-yield assets. ($1 = 106.0800 yen) (Reporting by Chang-Ran Kim Editing by Stephen Coates)