Japan on Saturday again delayed the launch of a rocket to deliver daily necessities to the International Space Station due to a problem in equipment.

The Japan Aerospace Exploration Agency had been scheduled to launch the H-2B rocket carrying the Kounotori7 cargo ship from the Tanegashima Space Center in southwestern Japan early in the morning, after postponing its launch on Tuesday due to inclement weather.

"We faced a rather serious issue," Koki Nimura, senior chief engineer of Mitsubishi Heavy Industries Ltd., which developed the rocket, told a press conference.

The latest decision followed a problem found in the valve to adjust pressure inside a fuel tank and it may take more than a week to fix the flaw, JAXA said.

The cargo ship will bring food and other necessaries to the ISS. The delayed delivery will not immediately affect the operation of the space station, according to the agency.