The State Department says North Korea has rescinded its invitation for a senior U.S. envoy to travel to Pyongyang to seek the release of a detained American.
Bob King, the U.S. special envoy for North Korean human rights, was due to travel from Tokyo to Pyongyang Friday to request a pardon and amnesty for Kenneth Bae.
Bae has been sentenced to 15 years of hard labor by the authoritarian state, accused of subversion.
Department spokeswoman Marie Harf said the U.S. is "surprised and disappointed by North Korea's decision" and remains gravely concerned about Bae's health.
King intends to return to Washington from Tokyo on Saturday.
The U.S. is seeking clarification on Pyongyang's decision — a further setback to U.S.-North Korean relations, already severely strained by concerns over Pyongyang's nuclear program.
