Former president Jimmy Carter arrived in Pyongyang Tuesday, the same day North Korea quit the International Atomic Energy Agency.
Carter will hold critical meetings on the dispute triggered by North Korea's refusal to allow international inspection of its nuclear program.
Carter is traveling as a private citizen, but clearly both North Korean and U.S. officials hope he will carry back important messages.
The State Department's Mike McCurry says Pyongyang's IAEA move "makes a very serious situation worse.
"It's entirely up to North Korea to defuse this situation" by cooperating with international inspectors, McCurry says.
But North Korea's U.N. counselor Han Song Ryol says, "Since we quit from the IAEA, the inspectors in the country have nothing to do any longer."
McCurry says forcing the inspectors to leave would influence the "type of further action that would have to be addressed in a draft resolution" on sanctions the United States plans to submit to the U.N. Security Council.
Today, U.N. Ambassador Madeleine Albright plans to begin consultations.
First targets of sanctions: membership in international organizations, technical aid and cultural exchanges - after a warning period.
Embargoes on arms, oil and finances will come next - if the North remains unyielding.
Warns North Korea's Han: "Sanctions should be regarded as the proclamation of war."
