Toru Hashimoto admitted Monday that his signature policy of merging the prefectural and municipal governments of Osaka had failed to gain enough support from voters, just hours after his overnight re-election as mayor.

"I cannot proudly say I have won public confidence in the Osaka metropolis plan," Hashimoto said at a meeting with senior city officials.

Hashimoto resigned as Osaka mayor last month, calling for a new election to prove he had public backing for his goal to create a wider Osaka metropolitan government. His plan envisages the integration of the administrative functions of Osaka Prefecture with the cities of Osaka and Sakai to form a government structure similar to Tokyo in April 2015.

The 44-year-old lawyer-turned-politician won the election Sunday, but he garnered just 377,472 votes — compared with 750,813 in the 2011 poll — as voter turnout plunged to a record low 23.59 percent amid an apparent lack of interest in the metropolis plan.

Hashimoto intends to publish a blueprint for the plan by this summer as promised during the election campaign.

"The plan will eventually be put to a referendum," Hashimoto said on Monday.