An American teenager says after a one-week stay in North Korea that authorities there welcomed his idea for a children's "peace forest" along the border with South Korea.
The only catch is that the United States must first negotiate a peace treaty to formally end the 1950-53 Korean War.
Thirteen-year-old Jonathan Lee told reporters upon his return to Beijing that he had been treated well in North Korea and was taken to see the Demilitarized Zone dividing the two Koreas -- the world's most heavily fortified border.
He said he was not able to meet with Kim Jong Il, but the North Korean leader was given a letter explaining the idea for a peace forest. He said North Korean officials liked his idea but told him it was only possible if a peace treaty was concluded first.
The United States and North Korea do not have formal diplomatic relations. The U.S. is engaged in joint naval maneuvers with South Korea which it says are intended to warn the North against aggression.
Four Americans have been arrested in recent months on charges of entering North Korea illegally. Three have been freed but Alijon Gomes, a 30-year-old former English teacher, has been sentenced to eight years of hard labor.
Lee, who was born in South Korea, had already attracted widespread media attention with pro-environmental activities including a cartoon called "Go Greenman." That prompted a meeting in 2007 with former South Korean president Kim Dae-jung, which inspired him to address the peninsula's problems.
Some information for this report was provided by AP, AFP and Reuters.