By Ben Blanchard and Greg Torode
BEIJING/HONG KONG (Reuters) - A major regional security conference is shaping up as a face-off between Asia's two biggest powers, as Japan sends its hawkish prime minister and China dispatches a feisty diplomat instead of the usual brass to counter Tokyo's more assertive message.
Japanese Prime Minister Shinzo Abe, who took office in 2012 promising to bolster the role of the nation's military, will deliver the keynote address at the annual Shangri-La Dialogue in Singapore at the end of the month.
Beijing is sending Fu Ying, a tough and articulate former deputy foreign minister now serving as chairwoman of the Chinese parliament's foreign affairs committee, who is expected to make the case that it is Japan, not an increasingly powerful China, which threatens regional security.
Sino-Japanese tensions over a string of Japanese-controlled islands in the East China Sea that are also claimed by Beijing spiked two years, ago shortly before Abe took office.
Relations were further strained when Abe last December visited Tokyo's controversial Yasukuni Shrine, where Japanese World War Two leaders convicted by an Allied tribunal as war criminals are honored along with millions of war dead.
"We understand that the Chinese are keen to continue participating and will be sending a strong delegation, and Fu Ying's appearance reflects that," said Tim Huxley, Singapore-based executive director of the International Institute of Strategic Studies (Asia), which organizes the event.
"Our impression is that Prime Minister Abe's speech will stimulate a lot of interest, not least in China, and understandably they want to be in a position to respond swiftly and appropriately," Huxley said.
China's foreign ministry said it was unable to confirm Fu's attendance.
China has yet to confirm who will head the delegation from the People's Liberation Army, Huxley said. China's defense ministry did not respond to request for comment.
A source familiar with China's foreign policy, speaking on condition of anonymity, said that Fu was a good choice to go and spar with Abe.
"She is well-versed in putting across China's position to an international audience," said the source.
A polished English-speaker - still a rarity among senior Chinese officials - Fu is no stranger to taking on Japan.
Fu attended the Munich Security Conference earlier this year, where she criticized Japan for what she said was its "denial" of its crimes during World War Two.
"She can be very charming but she can also be very tough," said a diplomatic source in Beijing. "She will give a robust response to anything Abe says."
Organizers of the forum usually invite a regional prime minister or president to give the keynote address. Last year it was delivered by Vietnamese Prime Minister Nguyen Tan Dung.
Abe, accompanied by his defense minister and national security adviser, will likely be carrying what has become a consistent message from the Japanese leader on the world stage since he took office: that Japan will stick to a peaceful path; that Tokyo wants to play a bigger role on the global security stage; and that all nations should follow the rule of law.
In a speech at the North Atlantic Council this month, Abe - pointing to the growing security tensions in the region - highlighted China's hefty defense spending, along with what he called Beijing's efforts to change the status quo by force in the East and South China Seas, where China has territorial disputes with Japan and Southeast Asian nations.
While Japan is wary of China's growing military assertiveness, Beijing is suspicious of Abe's efforts to loosen the limits of Japan's pacifist post-war constitution on its military.
Relations have also long been soured by Chinese resentment of Japan's wartime occupation of large parts of China and the belief that Japan has never properly atoned for its actions.
Unlike most other countries, China does not usually send a top-ranked official to the Shangri-La Dialogue. It has sent its defense minister only once - in 2011.
Last year China's most senior official at the forum was Lieutenant General Qi Jianguo, the People's Liberation Army's deputy chief of general staff, who used the opportunity to ease concerns about Beijing's intentions.
A series of moves by China have unsettled its neighbors in recent months, including the declaration of a new air defense zone in the East China Sea and a more confrontational stance in the disputed South China Sea.
Tensions rose in the resource-rich South China Sea last week after China positioned a giant oil rig in an area also claimed by Vietnam. Each country accused the other of ramming its ships near the disputed Paracel Islands.
(Additional reporting by Linda Sieg in TOKYO; Editing by Alex Richardson)