China and Japan should boost dialogue and contact to "properly tackle the East China Sea issue" and jointly ensure peace and stability there, President Xi Jinping told Japanese Prime Minister Shinzo Abe on Monday.

When the two met after the conclusion of the G20 Leaders Summit in Hangzhou, Zhejiang province, on Monday evening, Xi noted that the two-way ties are "disturbed by complicated factors from time to time".

Also, Xi said, "Japan should be cautious in words and actions with regard to the South China Sea issue and avoid posing a disturbance to the improvement of China-Japan ties."

Abe said Japan is willing to build mutual trust with China, earnestly improve bilateral ties and maintain dialogue over relevant issues.

Xi said the two sides should "reinforce a sense of duty and awareness of crisis", expand the positives in the ties and curb the negatives in order to ensure a steady thaw of ties.

Strain clouded relations when Japan took a high-profile position on the South China Sea issue earlier this year. Tension has also lingered around China's Diaoyu Islands in the East China Sea recently.

Gao Hong, a senior researcher on Japan studies at the Chinese Academy of Social Sciences, said, "Tokyo's sufficient sincerity and substantial actions are necessary" for a range of bilateral agenda items, including the building of two-way security mechanisms and free-trade agreement talks.

"Flashy words make no sense and make no difference," Gao said.

On two-way cooperation, Xi said both countries could boost macroeconomic policy coordination, pragmatic cooperation in various fields, grassroots friendship and local exchanges.

Advanced regional cooperation and joint efforts in addressing global challenges should also be achieved, Xi said.

Abe said that Japan hopes to boost cooperation with China in fields such as finance, trade and environment protection.