Nippon Life Insurance says it will acquire Resolution Life Group Holdings for 8.2 billion dollars. It's the largest takeover by a Japanese insurer. Bermuda-based Resolution runs insurance businesses globally, including the US, Europe and Australia.

President, Nippon Life Insurance Shimizu Hiroshi said "The US is the world's largest life insurance market. We wanted to have a company there as the core of our business abroad in the future."

Nippon Life aims to strengthen its overseas operations through the buyout. Its domestic market is shrinking as Japan's population declines.

The company already holds a roughly 23 percent stake in Resolution Life. It plans to make the equity affiliate a wholly owned subsidiary by between July and December next year.

Separately, the Japanese insurer said on Tuesday it had acquired 21.6 percent of Corebridge Financial for about 3.8 billion dollars. The company is an affiliate of insurance-giant American International Group, or AIG, which operates in 70 countries.

Nippon Life's overseas businesses accounted for 4 percent of its core operating profit in the last fiscal year. The firm expects the ratio to rise to 20 percent after its purchase of Resolution Life.