"This might be an intentional clash aimed at heightening tension ahead of Obama's trip," Kim told YTN television. "I believe North Korea is trying to show Obama the volatility of the peninsula. North Korea has demanded a peace pact be signed with the US to replace the truce agreement (which ended the 1950-53 war)." The NLL was drawn up unilaterally by United Nations forces at the end of the Korean War in 1953.
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