Since then, China has claimed that there was a tacit agreement on the Senkaku Islands issue during the normalization talks. During his official visit to Japan in 1978, Chinese President Deng Xiaoping said at a press conference that at the time of diplomatic normalization, “both sides agreed not to address this issue” and also suggested that the next generation would be smart enough to find a satisfactory solution for both sides. Several former Chinese and Japanese officials also reaffirmed the tacit 1972 agreement. In 2010, the Japanese government, under a new cabinet of the Democratic Party, broke its silence on this matter and denied that such an agreement – tacitly or not – with the People`s Republic of China on the islands ever existed. In return, the Chinese government considers Japan`s denial a “total breach of trust.” In 2012, when the Japanese government “nationalized” several islands by buying them from its Japanese private owner, China accused Japan of breaking the agreement “so as not to change the status quo.” To date, the question is whether there was a tacit agreement between the Chinese and Japanese leaders in 1972 and whether it has since been a violent dispute between the two countries, which reinforces the non-existing on the islands. Nevertheless, the declassification of diplomatic recordings may shed light on these controversial issues. In early January 2015, newly classified British documents revealed that Suzuki Zenko, then Prime Minister of Japan, received Prime Minister Margaret Thatcher in 1982 before his visit to China to discuss Hong Kong`s future status. Suzuki advised his British counterpart to speak directly with the Chinese head of state, Deng Xiaoping, because Japan had reached a fruitful agreement with deng to maintain the status quo on the Senkaku/Diaoyu and, in fact, to freeze the dispute. In the absence of further bilateral confirmation or clear registration, the actions or statements of one party may be considered by the other party as a violation of the tacit agreement. For this reason, Japanese observers regard the integration of the islands into Chinese sovereignty in its 1992 maritime law as a clear sign that it no longer respects the “agreement”, even if it had existed. Unfortunately, the Chinese government has not published a full record of the diplomatic normalization of 1972 or Deng`s visit to Japan in 1978. What we can read still leaves some ambiguity behind us.

The nature of a “tacit agreement” requires a delicate balance between appearance and substance. An unwritten agreement depends on the degree of trust between the parties directly involved and institutional reminders on both sides to convey it. When the main stakeholders are gone, the “agreement” can only survive thanks to the institutional memory within each government. After U.S. President Richard Nixon`s surprise visit to the People`s Republic of China (PRC) in 1972, Japan and the People`s Republic of China began negotiations that resulted in the establishment of diplomatic relations between the two countries and the separation of Japan`s formal relations with the Republic of China (ROC).