Japan is to set up an embassy in Tonga's capital, Nuku'alofa, next January.
The Matangi Tonga website reports the Deputy Secretary for Tonga's Ministry for Foreign Affairs, Tevita Kolo, as saying a team from Japan raised the possibility of an embassy two months ago and more recently another group has been scouting for residences for staff.
He says they are still looking for a venue for their embassy, but are particularly interested at acquiring a floor at the Reserve Bank of Tonga building.
Japan has a long relationship with Tonga, and over the years has implemented many development projects throughout the country, including roads, schools, village water systems and fisheries projects.
Japan has an embassy in Papua New Guinea and Fiji.