Washington (CNN) -- President Obama wrote a personal letter to North Korean leader Kim Jong Il that a U.S. envoy delivered, a senior U.S. official said Wednesday. Stephen Bosworth, U.S. special envoy for North Korea, delivered the letter for the North Korean leader during a three-day visit to North Korea last week, the official said. The official declined to be identified because of the sensitivity of the issue. Bosworth noted last week that, during his visit, he "communicated President Obama's view that complete denuclearization of the Korean Peninsula is a fundamental undertaking of the six-party process ... and that the absence of progress on denuclearization is an obstacle to improving our relations."
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U.S. envoy delivered Obama's letter while visiting North Korea, official says
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Special envoy Stephen Bosworth went to North Korea last week
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Bosworth visit called "positive," although it did not win promises from Pyongyang
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U.S. wants North Korea to return to six-party talks aimed at ending its nuclear program
She also has warned the United States will not normalize ties with Pyongyang or lift sanctions unless @placeholder takes irreversible steps toward dismantling its nuclear program.