Dhaka, Oct. 30 -- Prime Minister Tarique Rahman's Tokyo trip has ended with the promise of billions of dollars in potential Japanese investment and a renewed ambition to make Bangladesh a regional hub for trade, energy and industry.

The opportunity is substantial. Whether it delivers, however, will depend on how effectively the agreements are turned into projects and how carefully Bangladesh protects its interests.

During his four-day visit, which began on Oct 26, Tarique met Japanese Prime Minister Sanae Takaichi, held talks with business leaders and visited the operations of prominent Japanese companies.

Analysts have welcomed the preparations and commitments behind the trip, while stressing that the details of future agreements will...