Japan does not plan to mention, in revised guidelines on defense cooperation with the United States, the goal of acquiring the ability to attack enemy ballistic missile launch sites, a Tokyo government source said Sunday.

The United States has urged Japan to tread carefully on the matter, out of concern such a declaration could unnerve Japan's neighbors, especially China and South Korea, where the memories of Japanese aggression and colonization are still raw.

Tokyo will continue to take the stance that the matter requires further consideration, according to the source.