OSAKA (Kyodo) -- Japanese Prime Minister Shigeru Ishiba on Sunday pledged to ensure the success of the World Exposition in Osaka during a visit to the venue, as organizers face slower-than-expected advance ticket sales.

It is the first time since becoming Japan's leader in October that Ishiba has toured the site on the artificial island of Yumeshima, where construction of pavilions and other preparations continue with fewer than three months until the expo opens.

"We are committed to ensuring (the expo's) success, and have no concerns about ticket sales," Ishiba, who assumed the role of event's honorary chairman on Friday, told reporters following the visit.

Some 7.5 million advance tickets for the expo were sold as of early January, well short of the organizers' target of 14 million.

Ishiba acknowledged that while sales are currently not "outstanding," they usually pick up after the event opens, with many people visiting more than once.

During the inspection, he toured key facilities, including the government's Japan Pavilion and the Guest House for welcoming foreign dignitaries, to check on the overall progress of preparations.

He also met with Osaka Gov. Hirofumi Yoshimura to discuss strategies for boosting attendance and utilizing the venue following the expo.

Yumeshima Station, directly connected to the expo site, opened on Sunday, with over 130,000 people expected to use the new station on the Osaka Metro Chuo Line on a busy day.

A journey from the station to the major Tokaido Shinkansen bullet train station of Shin-Osaka takes about 40 minutes.

The Japan Association for the 2025 World Exposition expects 28.2 million visitors during the event from April 13 to Oct. 13, with ticket sales anticipated to cover the event's operational costs.

The site's construction cost has nearly doubled from the initial estimate to 235 billion yen ($1.5 billion), with the central government, the Osaka prefectural and municipal governments and the private sector each bearing one-third.