Interceptor missiles that will be jointly developed by Japan and the United States could be offered to third countries, Defense Agency Director General Yoshinori Ono said Thursday.

The issue is sensitive as Japan limits its export of arms due to its Constitution.

"If there is a request from the United States, it could be possible for those missiles to be provided to third countries under certain circumstances," Ono told a Diet panel. He was referring to a bilateral research project on sea-based interceptor missiles to counter a possible ballistic missile threat from North Korea.