UNITED States Vice-President Joe Biden has kicked off a three- nation visit to assuage growing concerns about Washington's Asia policy, but attention will focus largely on China's recent declaration of an air defence zone.
The White House said in a statement that Mr Biden, who arrived here late last night, would reaffirm the US-Japan alliance as a cornerstone of regional stability and stress the US' "enduring presence as a Pacific power" in meetings with Japanese leaders.
Observers expect Mr Biden and Prime Minister Shinzo Abe, who meet today, to send an unequivocal message to China that Japan and the US share a common stance on the Air Defence Identification Zone (ADIZ) issue.
China's new ADIZ, declared on Nov 23 without prior notice, overlaps part of Japan's own ADIZ and includes the disputed Senkaku islands, which the Chinese call Diaoyu and also claim.
Former defence minister Satoshi Morimoto said on a television news show yesterday: "Japan and the US are not quite together on this issue. The Abe-Biden meeting must send a clear and coordinated message to Beijing."
Some Japanese reports even said the message will ask Beijing to scrap its ADIZ.
Last week, the US sent two unarmed B-52 bombers into the Chinese zone. But it is believed the US wants to avoid getting involved in any territorial disputes over the Senkakus, raising doubts as to how serious it is about defending Japan against attacks by a third party, as provided for by their security alliance.
Reports yesterday said South Korea has decided to expand its ADIZ in response to the new Chinese zone, which also overlaps that of South Korea.
Beijing has kicked up a storm in the region with its insistence that all civilian aircraft passing through its new zone must provide it with flight data, even if they do not intend to enter Chinese national airspace.
Mr Abe told Japan's two largest air carriers not to do so. Japan Airlines and All Nippon Airways at first complied with his request, but later changed their minds.
In contrast, the US State Department advised US airlines to abide by rules put out by foreign governments.
Worried by Washington's stance, Tokyo said on Sunday it had confirmed that the US Federal Aviation Administration had not instructed US airlines to follow the Chinese rules.
After Tokyo, Mr Biden will travel to Beijing tomorrow, where he will hold talks with Chinese leader Xi Jinping.
He will then head to Seoul for talks with South Korean President Park Geun Hye.
He is also due to speak on the US-Korean Partnership and on US policy in the Asia-Pacific region at Seoul's Yonsei University.