A Japanese supply run to the International Space Station has been delayed again.
The countdown was halted Saturday local time in Japan, with only a few hours remaining before liftoff. Earlier in the week, a typhoon delayed the launch.
The Japanese space agency said there was an issue with the propulsion system. No new launch date has been set.
The cargo ship — the seventh to be launched by Japan — contains new batteries needed for a pair of NASA spacewalks.
NASA says the delay will cause the spacewalks — which had been scheduled over the next two weeks — to slip even further. The lithium-ion batteries will replace aging nickel-hydrogen batteries in the space station's solar-generating electrical system.
Five tons of supplies are loaded into the capsule named Kounotori, Japanese for white stork.