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Obama: N. Korean rocket test would isolate regime

President Obama visited the demilitarized zone between North and South Korea and said China should rein in its communist neighbor. NBC's Kristen Welker reports.

Updated at 7:50 a.m. ET: SEOUL, South Korea -- Warning North Korea from its doorstep, President Barack Obama said Pyongyang risks deepening its isolation in the international community if it proceeds with a planned long-range rocket launch.

"North Korea will achieve nothing by threats or provocations," Obama said during a news conference Sunday in Seoul, South Korea, where he was to attend a nuclear security summit.

Earlier on Sunday, South Korea said North Korea had moved a long-range ballistic rocket to its northwestern launch site in preparation for a launch, The Associated Press reported. North Korea has said it will launch a satellite into space on a long-range rocket next month as part of its peaceful space program.

Officials from the South Korean Defense Ministry and Joint Chiefs of Staff officials told the AP the information on the rocket came from the South Korean and U.S. militaries. They provided no further details and spoke on condition of anonymity, citing department rules.

Obama tells US troops at Korean DMZ: 'You guys are at freedom's frontier'

A White House official in South Korea told NBC News he could not confirm the rocket movement, saying he had not seen any U.S. intelligence reports on issue. Nobody would be surprised by such a provocation, however, the official added.

Obama spoke fresh off his first visit to the tense Demilitarized Zone, the heavily patrolled no-man's land between North and South Korea, where he peered long and hard at the isolated North.

"It's like you're in a time warp," Obama said. "It's like you're looking across 50 years into a country that has missed 40 years or 50 years of progress."

From the DMZ, Obama returned to Seoul for a private meeting with South Korean President Lee Myung-bak. Both leaders warned there would be consequences if North Korea proceeds with its plans to launch the long-range rocket next month, a move the U.S. and other powers say would violate a U.N. ban on nuclear and missile activity because the same technology could be used for long-range missiles.

President Obama paid his first visit to the tense zone separating North and South Korea amid new nuclear tensions. NNBC's Kristen Welker reports.

Obama said the launch would jeopardize a deal for the U.S. to resume stalled food aid to North Korea and may result in the tightening of harsh economic sanctions on the already-impoverished nation.

"Bad behavior will not be rewarded," Obama said. "There had been a pattern, I think, for decades in which North Korea thought if they had acted provocatively, then somehow they would be bribed into ceasing and desisting acting provocatively."

The planned rocket launch is yet another setback for the United States in years of on-again, off-again attempts to launch real negotiations. The announcement also played into Republican criticism that Obama had been too quick to jump at a new chance for talks with the North Koreans.

'Strong and prosperous nation'
North Korea wants to use the celebrations around Kim Il Sung's birthday on April 15 to showcase its emergence as a "strong and prosperous nation," even as millions go hungry and it begs for international aid. The North has planned a series of events to mark the centenary of the birth of the state's founder, including a rare ruling party conference and the controversial launch of the ballistic rocket.

Its vow to fire the rocket has put in jeopardy a deal struck in February with the United States to get food aid in return for a moratorium on long-range missile and nuclear tests.

The North's Foreign Ministry warned that it was "intolerable double standards" for some countries to assert that the North was the only nation not allowed to launch satellites while for the same countries, satellite launches were commonplace.

Analysis: Why N. Korea's planned rocket test matters

"If there will be any sinister attempt to deprive the (North) of its independent and legitimate right and put the unreasonable double standards upon it, this will inevitably compel the (North) to take countermeasures," the ministry said in a statement late on Friday.

North Korea has conducted two similar launches. The last one, in 2009, provoked outrage in Tokyo because the rocket flew over Japan. As it did three years ago, Japan says it is prepared to shoot the rocket down if it threatens its territory.

The rocket launch, which the United States and other countries say is the same as a ballistic missile test, is banned under U.N. resolutions.

Even China, North Korea's main ally, has expressed its worry over the launch, scheduled for between April 12 and April 16, and has urged the North to "stay calm and exercise restraint and avoid escalation."

The secretive North has twice tested a nuclear device, but experts doubt whether it yet has the ability to miniaturize an atomic bomb to fit inside a warhead.

NBC News, Reuters and The Associated Press contributed to this report.

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