Vice President Joe Biden is preparing to head to Beijing Wednesday, following talks in Japan about China's controversial Air Defense Identification Zone, or ADIZ.
After meeting Tuesday with Prime Minister Shinzo Abe, Biden told reporters the announcement of the new zone "has raised regional tension and increased the risk of accidents and miscalculations."
He said he intends to raise the issue of the ADIZ when he meets with Chinese leaders in Beijing.
In an interview in Tokyo, Biden urged both Japan and China to "establish crisis management and confidence-building measures to lower tensions." But Bonnie Glaser, a China expert at the Washington-based Center for Strategic and International Studies, says that is going to be difficult right now.
"And so it is quite difficult for Vice President Biden in this particular heightened, tense atmosphere, to try and urge the two sides to resume political dialogue and particularly to talk about confidence building measures between the two militaries."
China late last month set up its Air Defense Identification Zone, which overlaps with islands also claimed by U.S. ally Japan. Beijing has requested that all airplanes submit flight plans ahead of flying through the zone.
Speaking from Beijing, James Manicom, a research fellow at the Canada-based Center for International Governance Innovation, tells VOA's Victor Beattie that China's ADIZ differs from zones imposed by other countries in one major way.
"What makes China's different is that they apply the zone to any aircraft that are even transiting the zone. Whereas the U.S., Canada, Iceland, the UK, other countries that have these, typically only apply the identification requirements to aircraft that intend to enter their airspace. That's the problem. So it exceeds what other countries believe to be a responsible lien, if you like, on freedoms of international airspace."
The U.S. has repeatedly rejected the Chinese zone. Last week, it flew two unarmed B-52 bombers on "routine" training missions through the area, ignoring Chinese demands the aircraft identify themselves.
But Washington officials have recommended U.S. commercial airlines comply with China for the safety and security of passengers.
After visiting China on Wednesday, Biden will head to South Korea Thursday, which has also been angered by China's declared air defense zone.
He is expected to meet with President Park Geun-hye and visit the demilitarized zone with the North before returning to Washington.