BEIJING (AP) -- Emerging from a meeting with Chinese President Xi Jinping, U.S. Vice President Joe Biden said Wednesday that U.S.-China relations depend on trust and a positive notion of each other's motives. Neither leader made public mention of a major clash over disputed airspace that's pitted China against the U.S. and its Asian allies.
Appearing somber and subdued, Biden said the relationship between the two major powers will significantly affect the course of the 21st century. If the U.S. and China can get that relationship right, the possibilities are limitless, Biden said as reporters were allowed in briefly after he met with Xi in Beijing.
"This new model of major country cooperation ultimately has to be based on trust and a positive notion about the motive of one another," Biden said.
Biden said he had come to Beijing because complex relationships require sustained engagement at high levels. He said Xi's candor and constructive approach had left an impression on him.
"Candor generates trust," Biden said after a meeting that ran more than an hour longer than scheduled. "Trust is the basis on which real change -- constructive change -- is made."
The two leaders had a second meeting involving larger delegations and a working dinner planned for later Wednesday.
Absent from Biden's comments was any discussion of U.S. concerns over China's new air defense zone. Only a day earlier, Biden pledged to raise those concerns "with great specificity" with Xi and other Chinese leaders, adding that China's move was deeply concerning.
"This action has raised regional tensions and increased the risk of accidents and miscalculation," Biden said in Tokyo Tuesday after meeting with Japanese President Shinzo Abe.
Japan has been on edge for the past two weeks since China unilaterally declared any planes flying through the zone must file flight plans with Beijing. The airspace sits atop tiny islands that are at the center of a long-running territorial dispute between China and Japan.
The U.S. refuses to recognize the zone, but Biden has avoided calling publicly for Beijing to retract it, wary of making demands that China is likely to snub. Rather, the vice president hoped to persuade China not to enforce the zone or establish similar zones over other disputed territories.
After meeting with Biden, Xi said the U.S.-China relationship had gotten off to a good start this year "and has generally maintained a momentum of positive development." But he said the global situation is changing, with more pronounced challenges and regional hotspots that keep cropping up.
"The world as a whole is not tranquil," Xi said through a translator, adding that the U.S. and China shoulder important responsibilities for upholding peace. "To strengthen dialogue and cooperation is the only right choice facing both of our countries."
Added Biden, "The way I was raised was to believe that change presents opportunity."
At the start of his visit to Beijing, Biden urged Chinese students to challenge orthodoxy and the status quo, drawing an implicit contrast between the authoritarian rule of China's government and the liberal, permissive intellectual culture he described in the United States.
"I hope you learn that innovation can only occur where you can breathe free, challenge the government, challenge religious leaders," Biden told young Chinese citizens waiting at the U.S. embassy to get visitor visas processed.
Biden said he hoped they would learn during their visit that "innovation can only occur where you can breathe free."
"Children in America are rewarded -- not punished -- for challenging the status quo," he said.
Biden's comments were not immediately reported by Chinese state media and were not likely to be widely known in China. A one-minute excerpt of his speech posted by the Sina news website included Biden's comment about challenging the "status quo," but left out the one about challenging the government.
When Biden arrived later at the Great Hall of the People, a ceremonial edifice steps away from Tiananmen Square, any tensions between the U.S. and China were papered over as Chinese Vice President Li Yuanchao welcomed him with an elaborate honor guard. A military band played the two countries' national anthems as Biden and Xi stood amid the massive hall's marble floors and crisscrossing red carpets.
Associated Press writer Ian Mader contributed to this report.
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