Jeon Heon-Kyun/Pool / EPA
South Korean soldiers stand guard at the Military Demarcation Line in the Demilitarized Zone that separates the two Koreas since the Korean War, in the border village Panmunjom in Gyeonggi-do, South Korea.
President Barack Obama, seeking to increase pressure on North Korea to abandon its atomic weapons, will visit the Demilitarized Zone on South Korea's tense border on Sunday before a nuclear security summit in Seoul.
Obama's visit to the border will be a strong show of support for South Korea, the White House said on Tuesday, sending a message to the North as Washington builds an international effort to get stalled nuclear disarmament talks back on track.
North Korea will not attend the summit, where Obama will meet with Chinese President Hu Jintao and urge him to use Beijing's long-standing influence with Pyongyang, where leadership has recently passed to Kim Jong-un.
"We certainly hope and recommend that China bring all the instruments of power to bear to influence the decision-making in North Korea," said Daniel Russel, White House National Security Council senior director for Asia.
Ben Rhodes, deputy national security adviser, said the trip has two purposes for Obama.
"The first is the focus he has put on nuclear security along with non-proliferation since the beginning of his time in office," Rhodes said. "And the second is, of course, our increased focus on the Asia Pacific as a region of great importance to the United States."
Obama will meet with U.S. troops at the DMZ during the trip, his third to South Korea in three years, White House officials said.
Secretive North Korea has twice tested a nuclear device, and the United States says its long-range ballistic missile program is progressing quickly.
While experts doubt North Korea has the ability to miniaturize an atomic bomb to place atop a warhead, last year Washington warned that the American mainland could come under threat from North Korean missiles within five years.
Last month, North Korea reached an agreement with Washington to suspend nuclear tests, long-range missile launches and uranium enrichment as part of a deal to restart food aid, but then announced it would launch a rocket carrying a satellite to mark the centenary of founder Kim Il-sung's birth next month.
The United States has said this plan could violate the nuclear moratorium deal and scuttle the resumption of food aid.
This article includes reporting by Reuters.
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