Indonesia is turning to the yen market for a rare sale of blue bonds to raise funds for ocean-related projects.

The Southeast Asian country is marketing a Samurai deal which includes several blue bond tranches. It would be the first such issuance of yen-denominated debt from a foreign borrower, according to the underwriters. Japanese seafood company Maruha Nichiro Corp. also sold the country’s inaugural blue note last year.

Only a handful of issuers globally have sold blue bonds, which were pioneered by the island nation of Seychelles in 2018. The variant of green debt typically channels funds into areas such as marine conservation and improving water resources, underscoring some of the issues posed by climate change.

Even so, issuance has been scarce, especially with increasing scrutiny on the use of funds raised from environmental, social and governance debt.

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Proceeds from the Republic of Indonesia’s sale will fund investments in ocean conservation and climate change mitigation programs, according to a filing from the issuer. It’s the world’s largest archipelagic country, consisting of thousands of islands.

Some other sovereign issuers are exploring the Samurai bond market in order to tap yield-hungry Japanese investors, especially as the Bank of Japan’s ultra-dovish policy keeps rates anchored close to zero.