奥巴马4月访日菲等四国 重振亚太战略

Obama's visits to Manila and Kuala Lumpur are intended to make up for his no-show when he cancelled a previous Asia tour in October amid domestic political strife in Washington.

A subtext to his visit will be rising territorial tensions between several US allies and China, which deepened over Beijing's recent declaration of an "air defense identification zone" in the East China Sea.

Beijing was also angered last week when Washington stiffened its line on territorial disputes in the South China Sea, calling for adjusting or clarifying its claims.

Obama's stops in Japan and South Korea will also bolster close US alliances, at a time of aggravated political tensions between its two Northeast Asian friends.

It was an open secret that Obama would visit Japan in April, 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 also reflects 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 provocations.

It indicates that Obama is keen to avoid dealing a political slight to South Korean President Park Geun-Hye that could have occurred if he visited Tokyo and not Seoul.

Relations between the two nations were rattled by Abe's December visit to the Yasukuni Shrine, which honors war criminals among Japan's war dead.

Obama's Asia itinerary also includes one noticeable exception -- a stop in China. But he is expected to return to the region later in the year for regional summits in Australia, Beijing and Myanmar.

- 'Ongoing commitment' -

The White House said in a statement that Obama's April trip will highlight his "ongoing commitment to increase US diplomatic, economic and security engagement with countries in the Asia-Pacific region."

He will try to push negotiations on a vast Trans-Pacific Partnership free trade pact that would include 12 nations, and is seen by some observers as an attempt to meet the economic challenge of a rising China.

The president, however, may encounter some skepticism from regional partners because Senate Democratic Majority Leader Harry Reid, a key Obama ally, has expressed skepticism about granting him expanded powers to negotiate trade deals.

In light of Reid's remarks, Pacific Rim nations will be loath to make concessions in the trade talks, fearing that any deal agreed may be modified by the US Congress.

Obama will stop first in Japan, where he will meet Abe. Then he will travel to Seoul for talks with Park, likely to be dominated by North Korea's latest maneuvering on the divided peninsula.

Pyongyang is currently fuming at the prospect of annual US-South Korean military exercises starting later this month and that it views as an act of war.

From Seoul, Obama will head to Malaysia to meet Prime Minister Najib Razak to discuss deepening defense and military ties.

Obama will be the first US president to visit Malaysia since Lyndon Johnson in 1966. The Obama administration has been building on US efforts to cultivate closer ties with the country following the two-decade rule of former prime minister Mahathir Mohamad, who left office in 2003.

Obama's final stop will be Manila, where he will meet President Benigno Aquino and discuss evolving military relations designed to include rotations of US troops in the country.

The White House did not give exact dates for the trip, other than saying it would take place in late April. Obama is expected to be away for about a week.

- America's first 'Pacific president' -

Obama has declared he is America's first "Pacific president" and announced a rebalancing of military and strategic resources to the dynamic, fast-growing region.

But the cancellation of his trip last year, and the departure from his administration of big hitters committed to the Asia pivot like former secretary of state Hillary Clinton prompted concern in the region over US staying power.

Michael Green, who used to coordinate White House East Asia policy for president George W. Bush, said Obama must convince powers in Southeast Asia that his commitment remains firm in his second term -- amid impressions that Secretary of State John Kerry is more interested in the Middle East.

"Within Southeast Asia, they don't think that the new team has the same understanding, or commitment to the importance of ASEAN (Association of Southeast Asian Nations)," said Green, now with the Center for Strategic and International Studies.