Japan's planned development aid for India's Andaman and Nicobar Islands carries a "geostrategic overtone," with some security experts saying it is part of initiatives to keep an increasingly assertive China in check.

The ¥4.02 billion ($31 million) in aid comes as Japan and India have been promoting a "free and open Indo-Pacific" in coordination with the United States and Australia, the four regional democracies collectively known as "the Quad."

It marks the first time that India has accepted foreign assistance for development on the islands in the strategically important Bay of Bengal in the Indian Ocean, reflecting deepening ties between New Delhi and Tokyo.