Japan responded to North Korea's claims that it successfully test-launched long-range cruise missiles, saying if the missiles traveled one-thousand-500 kilometers, as reported in the North's official Korea Central News Agency, that they threaten the peace and safety of Japan and the surrounding area.

Japan's Chief Cabinet Secretary Katsunobu Kato said on Monday that Tokyo plans to collect the necessary data, conduct analysis and monitor the situation, in close cooperation with South Korea and the U.S.

Kato said based on the country's defense reinforcement guidelines, Tokyo will continue to strengthen its air and missile defense capabilities.

The Japanese official, however, said Tokyo has yet to confirm whether the North's missiles entered Japan's exclusive economic zone(EEZ) or territorial airspace.

Public broadcaster NHK assessed that Pyongyang likely conducted the tests to highlight its unchanged position regarding its missile development.

The broadcaster also took note of the launches occurring ahead of a meeting of the top nuclear envoys of South Korea, the U.S. and Japan in Tokyo this week to seek ways to jump start the denuclearization process.