Japan voiced hope for "mutually beneficial" ties with China's new leaders Thursday amid a bitter maritime dispute, but analysts said Beijing's territorial ambitions are unlikely to fade any time soon.
Relations between the two countries are some of the "most important... for Japan and China and for the whole world", said the foreign ministry's deputy press secretary Naoko Saiki in Tokyo.
"We really hope that the mutually beneficial relationship based on common strategic interests will be further developed and enhanced with the new leadership" of China, she said.
Saiki was speaking hours after China's Communist Party unveiled a new seven-man leadership council headed by Xi Jinping to take command of the world's most populous nation for the next decade.
North Korea, which counts China as its only major ally, was swift to respond, with leader Kim Jong-Un offering "warm congratulations" to Xi.
South Korea's foreign ministry said it hoped relations would continue developing under the new leadership.
Taiwan President Ma Ying-jeou sent Xi congratulations and said the two sides should "strengthen mutual trust and cooperate in good faith in response to new challenges".
Xi in his reply said China and Taiwan should "build a political, economic, cultural and social basis for the peaceful development of relations".
Taiwan's ties with China have improved markedly since Ma became the island's president in 2008.
Japan's relations with its giant neighbour are more troubled despite a trade relationship worth well over $300 billion a year.
Beijing says Tokyo has failed to atone for its brutal occupation in the 1930s and 1940s, while Japan maintains it is time to move on from events more than six decades ago.
In this combustible context, the row over who owns the Tokyo-controlled Senkaku islands, which Beijing claims under the name Diaoyus, has been thrust once more to the fore over the last few months.
Sometimes-violent street protests targeting Japanese businesses in China and a consumer boycott of Japan-brand goods have cast a shadow over the economic relationship, which analysts say neither side can really afford.
But, they say, a reset could be a long way off.
"Even though Xi wants to improve economic ties with Japan -- namely 'cool political ties, warm economic ties' -- the two countries obviously need a new start in the political arena," said Mitsuyuki Kagami, a China expert at Aichi University.
China's vast military machine, which has connections deep inside the government, is unlikely to allow this, he said.
"Given the huge military budget and interest groups related to it, it's difficult for China to change its current course towards becoming a military power."
Japan sees China's rising military as a threat.
Norihiro Sasaki, a China expert at the Institute of Developing Economies, said it would be "rational" for Xi to seek something of a new start with Tokyo.
However, he cautioned, Japan would continue to be a convenient bogeyman for Beijing.
"Given that China is still troubled by the huge gap between rich and poor and other factors of social instability, it will at times have to take a hard line against Japan to steer dissatisfaction away from the authorities towards foreign issues," he said.
Japan's own imminent political transition -- Prime Minister Yoshihiko Noda is expected Friday to dissolve parliament for an election on December 16 -- could be the key to better ties.
Sasaki said Beijing will make no effort to mend fences with Noda because he was the one who nationalised the disputed islands.
Despite his hawkish rhetoric "if (opposition chief Shinzo) Abe becomes prime minister, China will find it easier to move to mend ties".
"They expect him to act pragmatically once he becomes premier."