The Bay of Bengal Initiative for Multi-Sectoral Technical and Economic Cooperation (BIMSTEC) is a regional organization. China's Belt and Road Initiative (BRI) is a global infrastructure development strategy.
We need to identify the BIMSTEC member states that are not participating in the BRI.
Based on the current geopolitical and policy stances:
Other BIMSTEC members like Bangladesh, Myanmar, Nepal, Sri Lanka, and Thailand have engaged with the BRI in varying capacities.
Therefore, the BIMSTEC members not participating in China's BRI are India and Bhutan.
The Chagos Archipelago, recently in the news, is a disputed territory between which two countries?