A recent Kyodo News survey found that 82 percent of Japanese companies, sponsors and others involved said "fostering domestic momentum" would be a challenge
One of the largest wooden structures ever built is taking shape in Osaka, but hopes that Expo 2025 will unite the world are being dogged by cost blowouts and a lack of public enthusiasm.
The imposing circular centrepiece will be crowned by a 20-metre-high (65-foot) sloping canopy, designed by top architect Sou Fujimoto, known as the "Grand Roof".
It has a circumference of a staggering two kilometres and 161 countries and territories will show off their trade opportunities and cultural attractions at pavilions within the vast latticed ring.