In a surprise development with important implications for Osaka, a French newspaper reported Sunday that French Prime Minister Edouard Philippe will withdraw Paris's candidacy to host the 2025 World Expo.

Osaka, which is bidding for the event along with Baku, Azerbaijan, and Ekaterinburg, Russia, reacted cautiously to the news. Gov. Ichiro Matsui warned that the weekly newspaper Le Journal du Dimanche's report was not an official announcement.

"Even if the report is true, all it means is that the number of countries bidding has decreased from four to three. Osaka will continue to make strong efforts to win the Expo," Matsui tweeted late Sunday night.