Declassified documents showed Tokyo urged Chinese officials to refrain from publicly speaking about the disputed islands to avoid causing rift among the Japanese public.
Tokyo secretly asked Beijing not to make territorial claims to the Japan-controlled Senkaku Islands in the East China Sea to avoid friction ahead of the Japanese emperor's visit to China in 1992, according to to Japanese diplomatic documents declassified on Dec. 20
As the two nations mark the 50th anniversary of the normalization of diplomatic ties, military tensions and economic interdependence lie at the heart of their ongoing friction.