A year after Japan’s Democratic party won power vowing to work for a “relationship of trust” with China, debate over Beijing’s recent purchases of Japanese government debt has underscored the long-standing mutual doubts between east Asia’s leading powers.

Speaking to a Diet committee on Thursday, Yoshihiko Noda, Japan’s finance minister, noted with disapproval that Tokyo was still unable to buy Chinese state debt. He wanted Beijing policymakers responsible for recent JGB purchases to “clarify their objectives”.

There have been other recent Sino-Japanese sour notes. Just last month, Beijing appeared coolly dismissive of complaints from Katsuya Okada, Japan’s foreign minister, about the obstacles Japanese companies face doing business in China and a new Chinese rare earth export regime.