A Japanese high court on Friday rejected local residents' call to halt the operation of an idled nuclear reactor in western Japan, upholding a lower court decision.

The ruling by the Hiroshima High Court will allow the operator, Shikoku Electric Power Co., to continue utilizing the No. 3 reactor at the Ikata nuclear power plant in Ehime Prefecture, which has been suspended for a regular inspection through June 19.

File photo taken in November 2022 shows the No. 3 reactor at Shikoku Electric Power Co.'s Ikata nuclear power plant in Ehime Prefecture, western Japan. (Kyodo)

The appeal was filed by seven residents of Hiroshima and Ehime prefectures who live between 60 and 130 kilometers from the reactor.

The main focal point of the trial was whether the estimate of seismic ground motion, a key factor in a reactor's quake-resistance design, made by the utility was appropriate.

During court hearings, the residents said the operator's estimate was inadequate, arguing that a major accident could occur in the event of a powerful earthquake similar to one that devastated northeastern Japan in March 2011.

Shikoku Electric defended its estimate as taking into account the region's local characteristics including ground conditions, asserting there was "no particular danger."

In November 2021, the Hiroshima District Court dismissed a request by the residents to suspend the reactor, saying that merely citing the magnitude of earthquakes measured across the country does not indicate a similar earthquake will hit the area.