OSAKA (Kyodo) -- Osaka Mayor Hideyuki Yokoyama said Thursday the city and Osaka Prefecture have narrowed down the options for the future development of the 2025 World Expo site to a motor racing circuit and a water-themed resort facility.

The local governments will formulate a basic development plan based on the proposals by the end of March and hold a tender to select contractors in the latter half of 2025.

The racing circuit proposal was submitted by a group led by Obayashi Corp., while the resort idea was put forward by a group headed by Kanden Realty & Development Co.

Obayashi's plan includes preserving part of the "Grand Ring," the massive wooden roof structure and the event's symbol that will serve as the venue's main promenade. The ring uses approximately 27,000 cubic meters of wood.

The group plans to build hotels, a large arena and a racing circuit that could potentially host Formula 1 races in the future.

Kanden Realty's proposal includes hotels and a theater district, as well as a resort facility featuring water slides and pools. It aims to repurpose the ring's materials.

The site is located on the artificial island of Yumeshima, adjacent to a 49-hectare site on which an integrated resort featuring a casino is scheduled to open in autumn 2030.

"We aim to create an international tourist destination that carries on the Expo's vision," Yokoyama said, expecting it and the casino resort to complement each other.