U.S. Vice President Joe Biden is in Japan -- the first stop of a six-day Asian tour at a time of heightened tensions over China's newly declared air defense zone.

The White House says during his stops in Japan, China, and South Korea, Biden will stress the importance of avoiding actions that raise tensions and miscalculations that could undermine peace.

Biden will meet Tuesday with Japanese Prime Minister Shinzo Abe before heading to Beijing.

The White House says he will raise the issue of the air defense zone with Chinese President Xi Jinping and other officials.

Last month, China declared an air defense zone in the East China Sea over islands claimed by both China and Japan.

China is demanding all planes submit flight plans before crossing the zone. Japan refuses to comply.

The United States says the zone appears to be a provocative attempt to unilaterally change the status quo in the East China Sea. It also says it increases the risk of confrontation and accidents.

The United States does not recognize China's demands for flight plans and has already flown military jets across the zone. But it recommends U.S. commercial airlines comply with China for the safety and security of passengers.

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.