China's defense minister Liang Guanglie on Tuesday expressed the hope that the Diaoyu Islands issue with Japan will be peacefully resolved but he warned of "further action."

After his talks with US Defense Secretary Leon Panetta in Beijing, Liang told reporters, "We pay close attention to the development of the (Diaoyu Islands) issue and we reserve the right to take further action, but we hope the issue will be properly resolved through peaceful means and negotiations."

"I want to make it clear that the Diaoyu Islands are China's inherent territory, which is evidenced by history and law. Secretary Panetta and I discussed the issue in our talks," Liang said.

Liang said Japan is to be blamed for "heating up" the Diaoyu Islands issue when the Japanese government decided to "purchase" the islands.

The Chinese government and people have resolutely opposed the Japanese government's plans to "nationalize" the Diaoyu Islands, which is completely illegal, Liang said.

After a two-day visit to Japan, Panetta arrived in Beijing on Monday evening for his first visit to China as the Pentagon chief.

In addressing the media, Panetta didn't mention the Diaoyu Islands, but said, "It's in no country's interest for this situation to escalate into conflict that would undermine peace and stability in this very important region."

In another meeting with Panetta on Tuesday afternoon, Vice Chairman of China's Central Military Commission Xu Caihou also reaffirmed China's stance on the Diaoyu Islands.

"China opposes the claim that the Diaoyu Islands fall within the US-Japan security treaty," Xu said, urging the United States to honor its commitment of not taking sides on the sovereignty of the Diaoyu Islands.

Also on Tuesday, Chinese Foreign Ministry spokesman Hong Lei lodged representations to Japan over right-wing activists' landing on the Diaoyu Islands.

"Japanese right-wing activists' illegal landing on the Diaoyu Islands is a serious provocation that infringes upon China's territorial sovereignty, thus China has made solemn representations to Japan and demanded that the country explain its endorsement of right-wing activists," Hong said.

Hong urged Japan to take effective measures and stop any acts that may intensify tensions over the islands.

Tuesday marks the 81st anniversary of the "September 18 Incident," which directly preceded Japan's invasion of northeast China, with anti-Japan demonstrations springing up across the country.

"These demonstrations are spontaneous and aim to protest Japan's illegal 'purchase' of the Diaoyu Islands and condemn Japan's provocation of the outcomes of the victory of the World Anti-Fascist War and post-war international order," Hong said.

Since Japan's decision to "purchase" the Diaoyu Islands and affiliated islands on Sept. 10, the Chinese government has made solemn representations to Japan and taken a string of response measures, including announcing the Diaoyu Islands basepoints and baselines, sending surveillance ships to patrol around the islands and submitting the outer limits of its continental shelf.

"All these measures have effectively offset the legal consequences of Japan's illegal purchase of the Diaoyu Islands," Hong said.

"We urge Japan to face up to China's solemn position, listen to the Chinese people's just appeals and correct its mistakes," Hong said.

He also urged Japan to take a correct attitude and act properly, stop any acts that undermine Chinese territorial sovereignty, return to the understanding and common ground reached between the two countries and return to the track of negotiated settlement of the dispute.