By Osamu Tsukimori

TOKYO (Reuters) - A Japanese court on Friday upheld an order to keep two reactors at the Takahama nuclear plant closed, operator Kansai Electric Power said, leaving efforts to get a struggling nuclear industry up and running in limbo.

The court decision, upholding a petition from residents living near the plant concerned about safety, keeps the legal battle center stage in a struggle by Prime Minister Shinzo Abe's government to restore atomic power five years after the Fukushima disaster.

The Otsu District Court on March 9 ordered Kansai Electric, Japan's second-biggest utility, to shut down the reactors in Fukui prefecture west of Tokyo, in the country's first injunction to halt an operating nuclear plant.

The nuclear industry has only recently started to get reactors in a nuclear sector, which used to supply about a third of the country's power, back online amid widespread public opposition after the melt downs at Fukushima in 2011.

Friday's decision denied the utility's attempt to temporarily halt the shutdown order. Kansai has separately requested that the court revoke the injunction, and a decision on that is expected to come sometime soon, possibly by July.

"It is very regrettable that the petition for stay of execution was not approved," Kansai Electric said in a statement, adding that it hoped that the court would cancel the injunction soon.

Should Kansai Electric lose this legal fight, it will be left with the option of appealing to a higher court. That could mean months, or possibly a year, of delays and extra purchases of oil, gas or coal to replace nuclear power generation.

Japanese lower courts sometimes hand down contentious verdicts that are then overturned by higher courts, where judges tend to be more attuned to political implications, judicial experts say.

Amid mounting public scepticism over nuclear safety, local residents have lodged injunctions against nuclear plants across Japan.

Japan has 42 operable reactors but Kyushu Electric Power is the only utility that has been generating nuclear power after it was cleared to restart two reactors in southwestern Japan. In this case, legal action by residents failed to prevent the restarts of those reactors.

A Kansai Electric spokesman said the losses from the shutdown of the two Takahama reactors amounted to 10 billion yen ($96 million) per month because of higher fossil fuel consumption and other factors.

Shares in Kansai Electric were little changed after the news and were trading up 1.9 percent at 968.5 yen by 0332 GMT.

(Editing by Aaron Sheldrick and Ed Davies)