North Korea appears to be preparing to test-fire a long-range missile, South Korea's defence ministry said Monday, amid reports that a launch could come within weeks. "We have detected signs that North Korea is preparing to fire an ICBM (intercontinental ballistic missile)," a defence ministry spokesman told a foreign news agency. "US and South Korean intelligence authorities are still analysing the information," he said, declining to confirm a report by South Korea's Yonhap news agency that the launch could take place in one or two weeks. The North has moved a long-range missile to a launch base in Dongchang-ri along its northwestern coast, Yonhap quoted intelligence sources as saying. The North has another site at Musudan-ri on the east coast, from where it fired a long-range rocket over Japan on April 5. It said it put a satellite into orbit but other nations saw the launch as a disguised missile test.