(ATTN: UPDATES in paras 1-12 with details, background; ADDS new photos)
By Chang Jae-soon and Lee Haye-ah
SEOUL, March 25 (Yonhap) -- U.S. President Barack Obama warned North Korea on Sunday that the communist nation will put itself into deeper isolation, make promised food aid unlikely and face possible international sanctions if it goes ahead with a long-range rocket launch.
The threatened liftoff, if pressed ahead, will "only deepen North Korea's isolation, damage further relations with its neighbors and seriously undermine prospects of future negotiations," Obama said during a joint news conference after summit talks with South Korean President Lee Myung-bak.
"I'll simply say North Korea will achieve nothing by threats or by provocations," he said.
Obama's trip to Seoul came about a week after North Korea announced it will launch what it says is a satellite-carrying rocket next month, a pretext that Pyongyang has long used to disguise banned missile tests.
Military officials in Seoul said earlier in the day that the North is believed to have moved a long-range rocket to the launch site in Dongchang-ri in the country's northwest for final preparations for the threatened liftoff.
Obama said the North's rocket plan is a "direct violation of Pyongyang's own commitment," referring to last month's deal between Pyongyang and Washington under which the North promised to put a moratorium on nuclear and missile tests and halt uranium enrichment in exchange for 240,000 tons of food aid.
Obama said it will be difficult to ship the proposed aid if the rocket launch goes ahead.
"It would be difficult to move forward with that package" if the North is unable to meet commitments that it made "even a month earlier," Obama said. Such aid provision requires monitoring and "it's very difficult to have monitors in a period of tension and friction," he said.
North Korea should understand "bad behavior will not be rewarded," Obama said.
Obama also warned of possible international sanctions in case of a rocket launch.
Every time North Korea has violated U.N. Security Council resolutions, it has "resulted in further isolation, tightening of sanctions, stronger enforcement, greater support on the part of the international community for stronger enforcement," he said.
"I suspect that will happen this time as well," he added.
Lee also urged the North to call off the planned rocket launch, saying it is a violation of a U.N. Security Council resolution, and the nuclear freeze-for-food deal, and that Seoul and Washington will deal sternly with "any North Korean threats and provocations."
"The two countries agreed that North Korea's announcement of a planned long-range rocket launch is a violation of a U.N. Security Council resolution and an agreement between the United States and North Korea," Lee said. "Therefore, we concurred that North Korea should immediately withdraw the planned launch and abide by its international obligations."
Obama said that North Korea "still appears unsettled" after the death of Kim Jong-il, and it is "unclear who is calling the shots" and "what their long-term objectives are," raising questions about the new unexperienced leader Kim Jong-un, the youngest son of the late leader.
Upon arrival in Seoul earlier in the day, Obama made his first visit to the Demilitarized Zone on the heavily fortified border with North Korea, a symbolic a gesture underscoring Washington's security commitment to South Korea at a time of high tensions over the North's rocket plan.
"You guys are at freedom's frontier," Obama told a gathering of American troops during the visit to the DMZ, according to a pool report. "The contrast between South Korea and North Korea could not be clearer, could not be starker both in terms of freedom but also in terms of prosperity."
Dressed in a dark windbreaker jacket, Obama spent about 10 minutes at an observation post in the DMZ, looking at North Korea through field glasses and asking his military escorts where the demarcation line was in various directions, and the size of a North Korean village about 12 kilometers away.
About 28,500 U.S. troops are stationed in South Korea, a legacy of the 1950-53 Korean War.
Obama told the gathering of about 50 American troops that South Korean President Lee once confided to him that he was able to rise from poverty as a child to a successful career thanks in large part to America's military aid and support, drawing cheers from the soldiers.
North Korea claims that it has a sovereign and legitimate right to launch a satellite and its "space" program has nothing to do with the deal with the U.S. On Friday, Pyongyang said the launch plan has entered "a full-fledged stage of action."
The North also warned it will take "strongest countermeasures which no one can imagine" if South Korea "dares find fault with its nuclear deterrent and satellite launch and kick off" an anti-Pyongyang racket at next week's Nuclear Security Summit in Seoul.
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