PYONGYANG, May 21 (Xinhua) -- The Democratic People's Republic of Korea (DPRK) Monday accused Japan of challenging the atmosphere for regional peace and stability through military expansion and rewriting post-war constitution.

The official Korean Central News Agency (KCNA) said in a commentary that the ground and maritime Self-Defense Forces (SDF) are staging their first joint exercises aimed at overseas military operation.

Meanwhile, the moves for constitutional revision by the Japanese government are becoming "earnest" to scrap the country's commitment not to wage war, it said.

"The amphibious vehicle launch drill, landing drill, and airborne transport drill involving the amphibious task force and the first helicopter unit belonging to the ground SDF and the maritime SDF prove the nature of the drills to be of continental aggression, not 'self-defense,'" said KCNA.

At the same time, Japan has put into effect a "security legislation" involving the law on SDF which is drastically expanding the scope of operation by the SDF under the pretext of exercising the right to collective self-defense with the United States, said the commentary.

"Through the formation of an amphibious task force specializing in seizing remote islands and establishing the 'general ground force command' invested with the command of the ground SDF, the services and arms and commanding system of the Imperial Japanese Army are being revived," it added.