The Diaoyu Islands are a group of uninhabited islands located roughly due east of mainland China, northeast of Taiwan, west of Okinawa Island, and north of the southwestern end of the Ryukyu Islands. They are currently controlled by Japan, which calls them Senkaku Islands. Both China and Taiwan claim sovereignty over the islands.
Beijing cuts access to documents 'that support Japan's claim to Diaoyus'
Japan's Jiji Press news agency says the Chinese Foreign Ministry has been "strictly limiting" access to its archives since the start of this year because they might contain documents that support Tokyo's claim to the Senkaku - or Diaoyu - Islands.
In a story from Beijing, the agency reported that unidentified Chinese researchers said they suspected the limits on access had been imposed as a result of a document that a Jiji Press journalist had found in the archives in December.
Jiji said the 10-page document was a draft outline on territorial disputes to be used as the basis of a peace treaty with Japan that was produced by the Chinese government in May 1950.
Throughout the document, the Chinese reportedly refer to the disputed islands as the Senkakus and describe them as part of the Ryukyu chain, in modern-day Okinawa prefecture.
The document has been widely cited in Japan as evidence that China made no claim of sovereignty until reserves of oil and natural gas were located in nearby waters in the early 1970s.
In response to a query about why access was being restricted, Hong Lei , a spokesman for the Foreign Ministry in Beijing, told Jiji the archive was "in the process of updating its computer system for technical reasons".