China's Vice Minister of Commerce Jiang Weizeng said Thursday that the Japanese government's move to "purchase" the Diaoyu Islands would inevitably cast a negative impact on China-Japan economic and trade relations.

"It will be their right if Chinese consumers take action to demonstrate their stance in response to Japan's infringement upon China's territorial sovereignty," said Jiang during a State Council news conference.

Japanese products have already been dealt a blow since the two countries' relations soured in the past few months, with electronics giants seeing sales sharply dropping in August.

Meanwhile, Legal Daily reported on Thursday that a detailed illustration of the Diaoyu Islands as an inalienable part of China may be added to the new version of geography textbooks for grade eight students.

The Japanese consulate in Shanghai said Thursday that there have been six cases of Japanese citizens being attacked since the Japanese government signed the contract on Tuesday to purchase the Diaoyu Islands.

One Japanese person had noodle soup poured on him and received injuries to the eyes, while other people were beaten or had water bottles thrown at them, according to Kyodo News.

Also on Thursday, Japan's Yomiuri Shimbun reported on the Japanese government's plans for the Diaoyu Islands.

Plan A was to keep the islands untouched and plan H involved stationing Self-Defense Forces there. 

Despite the fact that Japanese Prime Minister Yoshihiko Noda previously favored plan B and plan C, which involved repairing a lighthouse, the Japanese government decided to keep the islands as they are to avoid further agitating China.

"Both sides need to calm down and solve the dispute," said Professor Akio Takahara, professor of Contemporary Chinese Politics at the Graduate School of Law and Politics, the University of Tokyo. "We need to keep the channel of communication open, more than ever."

Liu Jianping, an international relations professor at the Communication University of China, said that stopping "nationalization" of the Diaoyu Islands is the only way to save the current deteriorating Sino-Japanese relations.

Liu believes that Japan's explanation of purchasing the islands as a means to create a "stable and secure" environment is both deceitful and contemptuous, and one which the Chinese people would never accept.

US Defense Secretary Leon Panetta is planning to visit Japan next week to discuss the tense relations between Japan and South Korea and China, Kyodo News reported on Wednesday.

Separately, newly appointed Japanese ambassador to China Shinichi Nishimiya collapsed in Tokyo on Thursday morning, according to Kyodo News. Japan may assign another official to the post as Nishimiya is in critical condition, news portal ribenxinwen.com reported.