Asian allies are concerned over the US ability to focus on the region amid competing priorities, say analysts. The trip was an opportunity to reinforce the importance the US placed on Asia and to re-establish ties at the leadership level.
Obama's visit comes amid a "period of very significant tension among American allies, and between American allies and China," he added.
The President's trip - from 23-29 April - comes nearly seven months after he cancelled a visit to the region due to a government shutdown. Stops include a private dinner with Japanese Prime Minister Shinzo Abe, as well as bilateral meetings with the South Korean, Malaysian and Philippine leaders.
The US leader is expected to balance the need to bolster US ties with each Asian nation while improving communication among them, particularly between South Korea and Japan. The two Asian nations are at odds over disputed islands and historical issues linked to Japan's war history.
Moreover, on Tuesday, South Korea's defense ministry said that it had detected "a lot of activity" at the Punggye-ri nuclear test site. North Korea could be planning to hold a "surprise nuclear test or just pretend to stage a nuclear test", a spokesman said.
A state department spokeswoman said the US was "closely monitoring the situation." The test, if it went ahead, would be North Korea's fourth.
reporter
Park Sae-jin
swatchsjp@ajunews.com