By Miho Uranaka

TOKYO, June 30 (Reuters) - Japan's Dai-ichi Life 8750.T could double its strategic investment target to at least 600 billion yen ($4.17 billion) in its next medium-term management plan, the life insurer's CEO said, as the company looks to expand internationally.

Dai-ichi expects to accelerate its overseas investments after it acquired 15% of UK insurer and asset manager M&G MNG.L for around 160 billion yen in May, CEO Tetsuya Kikuta told Reuters in an interview.

The firm joins a host of Japanese financial institutions spending big on overseas acquisitions in search of growth as Japan's domestic market shrinks.

British firm Legal & General LGEN.L announced a tie-up with Meiji Yasuda in February, while Deutsche Bank's investment arm DWS is in talks to form a joint venture with Japan's largest insurer Nippon Life in India, Reuters reported in May.

Dai-ichi's current medium-term strategy, which runs for three years until March 2027, had targeted 300 billion yen for strategic investment.

Besides the M&G stake, the company has also invested around 100 billion yen in Australian finance group Challenger CGF.AX and upped its stake in UK hedge fund Capula Investment Management.

Dai-ichi's next strategy period is yet to be finalised but may run for four years, Kikuta said.

($1 = 143.9800 yen)

(Reporting by Miho Uranaka; Writing by Anton Bridge; Editing by Rachna Uppal)

((Anton.Bridge@thomsonreuters.com;))