He said Beijing has briefed Washington on the legitimacy, openness and defensive nature of the air zone and expects understanding, respect and coordination from the US.

On Tuesday in Tokyo, Biden called on Japan and China to find ways to reduce tensions, saying Washington was "deeply concerned" by the announcement of the zone.

He pledged to raise the issue directly when he met Xi.

However, Biden did not follow Japan by publicly calling for Beijing to retract the zone, or agree to issue a joint statement on this issue.

After Japan requested its airlines not to follow China's new air zone rules, the US government advised its airlines to notify Chinese authorities of flight plans to avoid misunderstanding.

Jin Canrong, a professor of international studies at Renmin University of China, said that Japan cannot be fully satisfied by Biden's assurance of support on Tuesday.

Japan's online media leader, the Nikkei Online Edition, said on Wednesday that "the Japanese government wants to contain China through cooperation with the US. ... But the US government believes that excessive partiality on Japan will draw opposition from China."

Tao Wenzhao, a senior research fellow on US studies at the Chinese Academy of Social Sciences, said Biden has tried to positively guide the impasse between China and Japan by highlighting the need for crisis management mechanisms between the two neighbors.

Jia Xiudong, a senior researcher of international affairs at the China Institute of International Studies, said: "Washington should not hold double standards for China and Japan on this issue. It is supposed to play a constructive role in reducing the tensions rather than fueling them."

Biden told Xi that Washington is greatly impressed by the decisions made during the Third Plenum of the 18th Central Committee of the Communist Party of China held in early November.

China's development is fully in the interests of US, he said.

The possibilities are endless if the US and China can get their relationship right, he said.

Later in the day, Xi held a banquet in Biden's honor.

Biden will have breakfast with US business leaders and meet Premier Li Keqiang on Thursday before leaving for Seoul.

Mo Jingxi contributed to this story.