North Korea has shut down its Yongbyon nuclear facilities, the United States announced on Saturday, saying Washington now hopes for ‘rapid progress’ toward Pyongyang’s nuclear disarmament.“The US has been informed on Saturday that the Democratic People’s Republic of Korea shut down its nuclear facilities at Yongbyon,” State Department spokesman SeanMcCormack said in a statement. “We welcome this development and look forward to the verification and monitoring of this shutdown by the IAEA team that has arrived in the DPRK,” he said.