TOKYO - Japan's Chief Cabinet Secretary Yoshihide Suga said here Friday that the country is mulling unilateral sanctions against the Democratic People's Republic of Korea (DPRK), which vowed to conduct a higher level nuclear test, local media reported.

Japan is considering its own sanctions as much as possible, Japan's Kyodo quoted Suga as saying, adding he hopes the UN Security Council could also adopts punishment against the DPRK.

The DPRK said it will conduct more rocket launches and a higher level nuclear test after the UN Security Council on January 22 approved a resolution condemning the DPRK's rocket launch in last December.

Japan has sanctioned the DPRK by imposing bans on trade and port calls.

On Wednesday, Japan froze assets of six organizations and four individuals related to DPRK's latest rocket launch, which Japan considered as a ballistic missile test, according to Kyodo.