Beijing vowed "zero tolerance" on Tuesday for any escalation by Japan that infringes on China's territorial sovereignty over the Diaoyu Islands in the East China Sea.
The remarks by a Foreign Ministry spokesman came in response to comments by Japanese Chief Cabinet Secretary Yoshihide Suga, who said earlier on Tuesday that stationing government personnel on the islands was one option being considered by Tokyo to assert its territorial claim.
"If the Japanese side deliberately resorts to provocations, it must shoulder all the consequences," spokesman Hong Lei said in Beijing on Tuesday.
Last year, the Japanese government announced it would "nationalise" part of the Diaoyu Islands, a move Beijing condemned as a major provocation. China has since beefed up patrols in the waters off the Diaoyu Islands to reaffirm its sovereignty.
"China's determination and strong will to safeguard sovereignty of the Diaoyu Islands is unswerving," said Hong, who called on Japan to stop further provocations and take tangible steps to resolve the conflict.
Ruan Zongze, vice-president of the China Institute of International Studies, said the expanded patrols have been effective as a countermeasure against Japan's provocations.
"The past year has witnessed China's aircraft patrolling the islands for the first time. Chinese patrol vessels have also managed to disperse Japanese vessels that were illegally operating or staying in the waters," Ruan said.
On Tuesday, a fleet from the China Coast Guard patrolled the islands, which Beijing described as a "regular operation" to exercise the nation's jurisdiction.
Liang Yunxiang, a professor of Japanese studies at Peking University, described the China-Japan relationship as "icy". He said much needs to be done before relations thaw, despite a recent informal talk between the leaders of the two countries.
Both nations have shown that they want to improve relations, but Liang said "neither of them has made any concessions on the sensitive issues."