BEIJING - China on Friday said it will take forceful measures in response to any moves that challenge the country's bottom line on sovereignty.

"We want to live in friendship with all countries including Japan, but we have to uphold our principles and bottom line," Chinese Vice Foreign Minister Zhang Zhijun told reporters Friday night.

Zhang said China pursues a policy of friendship and partnership with its neighboring countries and stays committed to the path of peaceful development.

"However, should anyone want to challenge China's bottom line on the issue of sovereignty, China will have no alternative but to respond forcefully so as to remove disturbance and obstacles and move steadily on the path of peaceful development," he said.

Zhang said Japanese government's "purchase" of the Diaoyu Islands, which was announced on September 10, constituted a grave violation of China's territorial sovereignty.

He said the move has caused "the most severe repercussions" on China-Japan relations since the two countries normalized diplomatic relations in 1972.

The Diaoyu Islands are part of China's territory in accordance with historical fact and law, Zhang said.

Japan has no right to buy or sell Chinese territory in any way and no transaction is allowed over even one inch of the Diaoyu Islands or anything on it, he said.

Zhang said the "purchase" farce had been orchestrated by Japan's right-wing forces. The Japanese government, instead of doing anything to stop the right-wing forces from violating China's sovereignty and sabotaging China-Japan relations, has stepped in and "purchased" the islands itself.

"What the right-wing forces had wanted to do and achieve was finally accomplished by the Japanese government," he said.

The dangerous political tendency of the Japanese right-wing forces had once plunged Asia into a major disaster. Such forces, if not stopped but used, if encouraged and indulged out of domestic political needs, will become further emboldened and lead Japan further down a dangerous path, Zhang said.

Some Japanese political figures have swaggered into the Yasukuni Shrine which honored WWII war criminals and paid tribute there without feeling guilty or ashamed, dismissing the feelings of the people in other Asian countries, which were victims of Japan's past aggression, he said.

If Japan cannot face up to history, cannot examine its conscience and sincerely correct its mistakes, no matter how developed its economy is, it will never stand up morally or psychologically, he said.

Zhang said China has expressed its adamant opposition to the illegal "purchase" of the islands from the very beginning. "Yet the Japanese government has turned a deaf ear to China's warning."

The Chinese government has taken a series of forceful measures to safeguard its territorial sovereignty. No external threat or pressure could weaken, not even in the slightest way, the resolve of the Chinese government and people to uphold China's territorial sovereignty, he said.

China and Japan have maintained contact and consultations on the issue of Diaoyu Islands through various channels and in different forms. The two sides started vice foreign ministerial-level consultations on Diaoyu Islands in Beijing on September 25.

In the contact and consultations at all levels, China has stated its government's solemn position on the issue and strong determination to safeguard territorial integrity, Zhang said.

China has urged Japan to have a correct reading of the situation, abandon any illusion and face up to reality. Japan should correct its mistake with credible steps and make real efforts so that the current problem will be handled properly, he said.

"We do not want to see the situation spin out of control. But this, however, is not to be decided by the Chinese side," Zhang said.

He demanded Japan take seriously China's solemn position and major concerns, and stop all actions that undermine China's territorial sovereignty.