Japan is set to further delay the launch of its new flagship H3 rocket due to newly discovered defects, sources familiar with the matter said.

The first flight of the H3 rocket had been postponed for a year from the launch date initially scheduled for some time in fiscal 2020, which ended last March, and was scheduled to take place by the end of this March.

But the discovery of defects forced the Japan Aerospace Exploration Agency (JAXA) to delay it a second time as it remains unclear by when the vehicle's engine can be redesigned and produced, the sources said Monday.