Some 47.8 percent of Osaka voters oppose a plan to turn the city administration into a metropolitan government similar to Tokyo's and 39.5 percent support it, according to a poll one week before the matter will be put to a referendum.

The third weekend telephone survey, conducted Saturday and Sunday by Kyodo News, found that opposition has fallen slightly since the previous survey conducted April 4 and 5, when 47.5 percent opposed the plan and 36.7 percent backed it.

In the first survey in mid-March, supporters and opponents were nearly even at 43.1 percent and 41.2 percent, respectively. No margin of error was given.

If approved in next Sunday's referendum, the city will be reorganized into five special wards in April 2017. Each ward will have its own mayor and assembly chosen by election.

In the latest survey, 32.1 percent said they saw no merit in the plan and 14.6 percent said they do not think it will improve residential services. Among supporters, 41.0 percent said bold reform is necessary and 27.7 percent cited the need to overhaul overlapping administrative operations.

The random-dialing survey contacted 1,490 households and received responses from 1,023 voters.

Osaka Mayor Toru Hashimoto, whose initiative to create a metropolitan government led to the referendum, has signaled he will retire from politics if the plan is rejected in the referendum. He is a top adviser to Ishin no To (Japan Innovation Party), the second-largest opposition party in the Diet.

Hashimoto says the plan will cut costs by streamlining redundant operations in the city and prefectural governments, with the special wards designed to focus on basic services, such as welfare, and the prefecture on infrastructure and other wider administrative operations.