Japan has lodged a protest against China's creation of a digital museum laying out its claims to a group of Japan-controlled islets in the East China Sea, the government's top spokesman said Monday.

"The Senkaku Islands have been recognized historically and under international law as an inherent part of Japan's territory and we maintain effective control over them," Chief Cabinet Secretary Katsunobu Kato said at a press conference.

China is "not in a position" to create such a website regarding the islets, Kato said, adding that Japan has demanded through diplomatic channels that it be taken down.

The dispute over ownership of the uninhabited islets, which China calls Diaoyu, has often strained Japan-China relations. China frequently sends coast guard or government ships to nearby waters in a bid to push its claims to them.

The digital museum can be viewed here: http://www.diaoyudao.org.cn/dydbwg.html

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