President Barack Obama needs to include South Korea on his itinerary for an Asia tour in April, a group of Korea experts here said Friday.

In an op-ed piece in the Washington Post, Richard Armitage, Victor Cha and Michael Green said Obama is expected visit Japan, the Philippines and Malaysia. The White House announced the president will travel to Asia in April but has not made public specific stops yet.

All three nations deserve Obama's attention but "a trip without South Korea would send the wrong signal" to the international community, they said.

They pointed out the world is watching the president's words and deeds to see if the U.S. really has staying power in Asia.

"Visiting key treaty allies Tokyo and Manila, while skipping another key ally, South Korea, on Obama's first trip to Asia of his second term would be an embarrassment for South Korean President Park Geun-hye, particularly given how prickly relations are between Tokyo and Seoul," they said.

The trio stressed the importance of maintaining close ties with the allies, especially amid the possibility of North Korea taking provocative acts.

South Korea and the U.S. also have some urgent bilateral issues to address, such as renewing a civilian nuclear accord and finalizing consultations over the transfer of wartime troop control.

On the trade front, South Korea has expressed interest in the Trans-Pacific Partnership (TPP) talks.

The experts with experience in working at a U.S. administration suggested Obama take the initiative, rather than "lead from behind," in dealing with those issues.

If the administration's "heralded rebalance to Asia is to have meaning, Obama must be at the front on diplomacy, trade and security," they said.

Armitage, president of Armitage International, served as deputy secretary of state from 2001 to 2005.

Cha, Korea chairman at the Center for Strategic and International Studies (CSIS), was director for Asian affairs on the National Security Council (NSC) staff for three years from 2004.

Green, senior vice president for Asia and Japan chairman at CSIS, worked as senior director for Asian affairs on the NSC staff from 2001 to 2006.

(Yonhap)