Tokyo announced twice in the past two days the possibility of dispatching troops to the Diaoyu Islands, a move Beijing on Friday slammed as "extremely irresponsible".

Analysts said Japanese Prime Minister Yoshihiko Noda and his cabinet have taken one of the most hawkish positions in recent years over the islands, and the move will leave Noda less room to improve bilateral ties.

Japanese Defense Minister Satoshi Morimoto on Friday indicated the possibility of mobilizing the country's Self-Defense Forces when commenting on Chinese vessels sailing near the islands in the East China Sea.

Morimoto said that the dispatch of troops is "secured by law", Tokyo Broadcasting System reported.

Morimoto's remark came a day after Noda announced a similar stance on Thursday.

Noda said that the Japanese government, if necessary, should take "resolute actions" against any "illegal" incursion of neighboring countries into Japan's "territorial waters".

Beijing on Friday expressed serious concern and strong objections over the "extremely irresponsible remarks" by Japan.

"Nothing can change China's strong will and determination to safeguard its territorial sovereignty," Foreign Ministry spokesman Hong Lei said.

Zhou Yongsheng, an expert on Japanese studies at China Foreign Affairs University, said Noda and Morimoto's recent remarks show that Tokyo's stance on the Diaoyu Islands issue is becoming tougher with less room for diplomatic maneuverability.

As the Japanese election draws near, some politicians such as Noda care little about China-Japan relations and "place priority on winning the election", said Zhou.

Shen Shishun, an expert on Asia-Pacific studies at Haikou College of Economics in Hainan province, said there is little chance that Tokyo will send its troops to the islands.

"In spite of the strong remarks from Japanese politicians, the government has not yet made up its mind to really send in troops," said Shen.

Hong said some politicians in Japan have expressed a willingness for a diplomatic resolution.

Japanese Cabinet Secretary Osamu Fujimura, the government's top spokesman, on Friday said the prime minister merely responded to a hypothetical question and was "referring to a theoretical possibility" of military action.

"(Noda's remark) was not specifically directed at containing China," Mainichi Daily Newspaper reported Osamu as saying.

Analysts said Tokyo's mixed responses reflect its desire to not rule out diplomacy.

"Some politicians, such as Noda and Morimoto, use strong rhetoric as a political tool for votes," Shen said.

Zhou warned that Japan may continue to take a hard line approach on the issue.

Bilateral ties deteriorated after Tokyo Governor Shintaro Ishihara initiated a plan in April to "purchase" the islands from a so-called "private owner" and Noda announced a plan to "nationalize" the islands in early July.

"A small group of individuals in Japan have deliberately created friction with China over the Diaoyu Islands and inflamed tension between the people of both countries. It is extremely wrong and hazardous," the Chinese embassy in Japan said on Thursday.

In another development, the International Olympic Committee appointed Japanese Olympic Committee President Tsunekazu Takeda a member of the IOC.

According to Kyodo News Agency, Ishihara's remarks have triggered dissatisfaction from some IOC members from Asia. Ishihara "should shut his mouth", Kyodo quoted an Asian veteran member as saying.

Support from Asian countries for Tokyo's bid to host future Olympic Games is indispensable, Kyodo said.

Contact the writers at zhangyunbi@chinadaily.com.cn and zhouwa@chinadaily.com.cn.