Biden, in Japan, Calibrates Message Over Tensions With China

TOKYO — Vice President Joseph R. Biden Jr. delivered a carefully-calibrated message of support to Japan on Tuesday, saying the United States had deep concerns with a new air defense zone created by China but stopping short of a demand that Beijing roll it back.As he began a weeklong trip to Asia that will take him to Beijing, Mr. Biden found himself in the midst of an increasingly tense standoff between Japan and China over Beijing’s creation of a zone of restricted airspace over contested islands in the East China Sea.

Administration officials insisted there was no daylight between the United States and Japan on how to respond to China’s move, despite the Federal Aviation Administration’s advice to American carriers to identify themselves when entering the restricted zone. The Japanese government has instructed its carriers to ignore the Chinese demand.

Although the Obama administration registered its displeasure with China’s so-called air defense identification zone by sending two unarmed B-52 bombers on a mission through it, federal regulators, as a safety precaution, advised American civilian flights to identify themselves before entering the airspace — in compliance with the Chinese regulations.

That was viewed by some in Japan as a mixed message, since the Japanese government had told its airlines to ignore the Chinese demand. Japanese newspapers began worrying about “allies no longer walking in lock step,” and government officials sought clarification from Washington.

The State Department quickly said that the advice did not mean that the United States was recognizing the air defense zone. And American officials have told the Japanese that the Federal Aviation Administration’s decision was a safety recommendation — far short of an order, though major American airlines said they were heeding it.

Still, a lingering ambiguity has led Japanese officials to give contradictory assessments of American intentions. On Sunday, Prime Minister Shinzo Abe told reporters that his government had confirmed through “a diplomatic route” that the United States had not asked airlines to file flight plans with the Chinese.