Japan hopes to improve its relationship with China following the appointment of a new leadership team under President Xi Jinping, Tokyo's top spokesman said Wednesday.

Chief Cabinet Secretary Yoshihide Suga offered his congratulations to the five new members of the seven-strong Politburo Standing Committee, citing the 45th anniversary this year of the normalization of bilateral ties. The relationship between the two countries have been chronically strained by territorial and historical issues.

"We want to further the improvement of ties from a comprehensive perspective, while appropriately dealing with outstanding issues and pressing forward with cooperation and exchange in every field through a strategic, mutually beneficial relationship," Suga told a news conference.

Asked about how the fortification of Xi's power might affect China's expansionary activities in the East China Sea, where Beijing claims the Japan-controlled Senkaku Islands, Suga said the government will continue to maintain surveillance and vigilance around the uninhabited islets, which China calls Diaoyu.

He reiterated the stance that the Senkakus are Japan's inherent territory and there is therefore "no issue of sovereignty that ought to be resolved."

Suga also said the government is still trying to arrange a summit between Prime Minister Shinzo Abe, South Korean President Moon Jae-in and Chinese Premier Li Keqiang in Japan before the year's end.

It was Japan's turn last year to host the trilateral gathering before it was put off amid a corruption scandal involving South Korea's then President Park Geun-hye.