Transcript for Kim Jong Un visits China in historic first

details coming up. Breaking news, that meeting overseas. North koan leader making that surprise visit to China in extreme secrecy. His first trip out of the country since he took power. Martha Raddatz has the latest. Good morning, Martha. Reporter: Good morning, robin. It was mysterious, surprising and historic, as you said. This is the first trip Kim Jong-un has taken outside of North Korea since he took power in 2011. Rumors had been swirling for days that Kim was in China after a heavily guarded armored train arrived in beijing, but the meeting was confirmed only after Kim left. But this morning China is releasing these images of the welcoming ceremony and banquet held for Kim and his wife. The meeting came at the invitation of China's president XI jinping who said Kim told him he was open to a potential meeting with president trump and was committed to the denuclearization of the Korean peninsula. Kim is believed to have nuclear weapons that could reach the U.S. And just a short time ago president trump reacted to the meeting tweeting for years and through many administrations everyone said that peace and the denuclearization of the Korean peninsula was not even a small possibility. Now there is a good chance that Kim Jong-un will do what is right for his people and for humanity. Look forward to our meeting. But trump then tweeted that in the meantime, maximum sanctions and pressure must be maintained at all costs. Talk about the meeting that took place in China. It appears that this is all taking place at a time when North Korea is said to be firing up a new nuclear reactor. Reporter: That's right, robin. Reports this morning in satellite images show emissions from a smokestack that indicate that North Korea is finally activating its new reactor the yongbyon. More things to negotiate if and when that meeting actually happens. Also at the white house this morning, president trump now

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