Gao also observed that some political voices within Japan are claiming that the September events are stoking "anti-Japanese sentiment", adding that Beijing already has reiterated that the events are not targeting any specific third party.

Feng Wei, a professor of Japan studies at Fudan University in Shanghai, said Tokyo "is truly willing to boost its relationship with Beijing", yet a major turnaround of the thorny ties would "take quite a period of time" and only "be achieved slowly and gradually".

On Monday, US State Department spokesman John Kirby said these are sovereign decisions that nations have to make. "We are going to respect these decisions," he told the daily press briefing.

Kirby made similar comments last week when he was asked about President Park Geun-hye's planned visit to Beijing from Sept 2-4 to attend the war anniversary, although Park may skip the military parade.

There have been reports by Japanese news media that US officials have been pressing President Park not to attend the Chinese commemoration activities, but US officials dismissed them.

Many US officials and pundits have worried that the growing relationship between China and South Korea will jeopardize the US-South Korea alliance, especially at a time when Japan and South Korea, two key US allies in the region, are at odds with each other over Abe's revisionist views on its World War II history.

Kirby also said on Monday that he doesn't have anything to announce with respect to the US attendance in Beijing for the war anniversary.

China and the US were allies during World War II. The Flying Tigers, composed of American pilots, were well known among Chinese for helping fight Japanese invaders in China.