Japan's military has drawn up a defense plan that refers to the possibility of an invasion by China, the Asahi Shimbun national daily said yesterday.
In one scenario, drawn up at a time of tense relations between Tokyo and Beijing, China occupies the disputed islands known as the Senkakus in Japan and the Diaoyu islands in China.
In another scenario, the plan reportedly also lays out the possibility of a military conflict between China and Taiwan, with the US backing Taiwan.
In the scenario, Japan would support such US operations and might come under attack from China.
However, the top-secret plan, drawn up by senior officers in what Japan calls the Ground Self-Defense Force, says there is only a slight possibility of an attack by China, the paper said.
The plan laid out various possibilities for a period between last year through 2008 and is considered a national secret, the newspaper said.
Although the plan does not expect a Japan-China conflict to become a serious possibility, it shows for the first time that Japanese defense officials formulated military strategies to counter China, the Asahi said.
This reflects a shift from their previous focus on a possible Soviet attack in northern Japan, it said.
The report comes weeks after a separate Japanese defense white paper referred to the need to monitor Chinese military modernization, sparking an angry reaction from Beijing.
Japan and China are at loggerheads over a range of issues from rights over natural resources in the East China Sea to the way World War II history is taught in Japanese schools.
Earlier this month, Japan said it had sighted five Chinese warships in the East China Sea, where China is developing a gas field close to an area also claimed by Japan.