UN inspectors have verified that North Korea has shut down its sole functioning nuclear reactor, the chief of the watchdog agency said Monday, confirming Pyongyang's first step to halt production of atomic weapons in nearly five years. "Our inspectors are there. They verified the shutting down of the reactor yesterday," said Mohamed ElBaradei, chief of the International Atomic Energy Agency. "The process has been going quite well and we have had good cooperation from North Korea. It's a good step in the right direction," ElBaradei said, speaking in Bangkok ahead of an event sponsored by Thailand's Science Ministry. North Korea pledged in an international accord in February to shut the reactor at Yongbyon and dismantle its nuclear programs in return for 1 million tons of oil and political concessions. However, it stalled for several months because of a separate, but now-resolved dispute with the US over frozen bank funds.