TOKYO — A nuclear reactor in western Japan began starting back up on Tuesday after a month’s hiatus, the first reactor in the country closed for any reason to win approval from a local government to resume operations since the Fukushima nuclear disaster.

Since the March 11 earthquake and tsunami that set off the nuclear disaster, a popular backlash against nuclear power has halted the reopening of reactors closed because of damage at the time or unrelated glitches, or for routine inspections. Regulations require reactors to close at least every 13 months for checks, meaning more and more reactors have gone out of service, with none allowed to restart — until Tuesday.

Only 10 of Japan’s 54 reactors are now generating electricity, a sharp reduction for an industry that once supplied 30 percent of the country’s electricity. The shortfall in supply forced the Tokyo Electric Power Company to tell companies to slash energy use by 15 percent this summer.

The government has been keen to soothe local jitters about nuclear energy and enable reactor restarts. But power companies must submit results of “stress tests” that evaluate a reactor’s defenses against earthquakes, tsunamis, station blackouts and the loss of water for cooling — and they must get a go-ahead from local the government.