Prime Minister Shinzo Abe sent a senior government official to a secret meeting between former Prime Minister Yasuo Fukuda and Chinese President Xi Jinping in Beijing in late July, sources close to Japan-China relations said Sunday.

Shotaro Yachi, the top bureaucrat in the National Security Council, accompanied Fukuda in an apparent attempt to realize the first formal meeting between Abe and Xi on the sidelines of the Asia-Pacific Economic Cooperation forum summit to be held in Beijing in November, they said.

The two leaders have yet to hold one-on-one talks since taking office — Abe in December 2012 and Xi the following March — as bilateral ties have plunged to the worst level in decades due to an ongoing territorial dispute over the Japanese-controlled Senkaku Islands in the East China Sea, and differing perceptions of wartime history.

Abe is considering dispatching Yachi to Beijing again soon to lay the groundwork for a bilateral summit, the sources said.

In July, Fukuda and Yachi conveyed Abe's intention to work for the improvement of bilateral ties to Chinese State Councilor Yang Jiechi and Foreign Minister Wang Yi.

In the July meetings, China maintained that talks between Abe and Xi can only take place if Tokyo acknowledges that a dispute exists over the sovereignty of the Senkakus, which China claims and calls Diaoyu, according to government sources.

Beijing also demanded that Abe promise not to visit the war-related Yasukuni Shrine in Tokyo, which honors Japanese World War II leaders convicted as war criminals along with the country's war dead, while he serves as prime minister.

Abe visited the shrine last December, angering China and South Korea, which suffered Japan's wartime aggression and view the Shinto shrine as symbolic of the country's militarist past.

Abe, meanwhile, is calling for a summit with Xi without prior conditions.