This missive is the latest salvo between the two neighbours ever since Japan discovered a Chinese consortium building a drilling rig on the Chinese side of its Exclusive Economic Zone.

In a statement China’s Foreign Ministry spokesperson Zhang Qiyue said, “China is deeply concerned about Japan’s decision on this issue. China has always held that the two countries should solve their border disputes in the East China Sea through negotiations.”

“We hope Japan can proceed from the general situation of bilateral ties and stability in the East China Sea area, taking a prudent approach and dismissing any actions that could harm China’s interests and complicate the situation,” she added without elaborating further.

The two nations have been disagreeing for a while now where exactly the nautical borders lie. Japan insists the border lie at the halfway point between the coasts of China and Japan. China insists on following international custom and states its border ends where the continental shelf ends.