Obama to tour Asia in April

US President Barack Obama will travel to Japan, South Korea, Malaysia and the Philippines in April, the White House says.

The visit is intended to quell doubts in the region about Obama's strategy of rebalancing US power to Asia, following the cancellation of his last planned trip there in October for domestic political reasons.

"The president will travel to Japan, the Republic of Korea, Malaysia and the Philippines in late April as part of his ongoing commitment to increase US diplomatic, economic and security engagement with countries in the Asia-Pacific region," the White House said in a statement.

Obama is expected to return again to Asia later in the year for regional summits in Australia, Beijing and Myanmar.

The White House announced in November that Obama would return to Asia to make up for his cancelled visit, which included planned stops in Manila and Kuala Lumpur.

And it was an open secret that he would call in Japan, too, to take up an invitation from Prime Minister Shinzo Abe, who took office in December 2012.

But the decision to add South Korea to the trip came after rising pressure from Seoul and from the Asia policy community in Washington.

The move may reflect a desire to signal to North Korean leader Kim Jong-Un that there are no gaps in US and South Korean resolve to counter Pyongyang's nuclear program and belligerent rhetoric.

It may also indicate that Obama is keen to avoid dealing a political slight to South Korean President Park Geun-Hye that could result from a presidential visit to Tokyo and not Seoul - during a time of aggravated relations between the two key allies.

Obama's Asia itinerary also includes one noticeable exception - a stop in China.

But his tour is likely to be dominated by questions over Beijing's territorial claims in the East and South China Seas that conflict with those of several Southeast Asian nations - including the Philippines.