SEOUL (BLOOMBERG) - The United States and Japan led protests on Monday (Sept 5) after North Korea fired three ballistic missiles off its east coast, all of which flew about 1,000km before landing in the sea.
At least one entered Japan's air defence zone, South Korea's joint chiefs of staff said.
The launches of what are believed to be mid-range Rodong missiles came during a meeting of global leaders at the Group of 20 summit (G-20) in China. The firings suggest that North Korea is continuing to make progress in the development of its missile technology.
White House National Security Council spokesman Ned Price said that US officials were "closely monitoring these latest provocations".
Japan said the firings were a clear violation of United Nations Security Council Resolutions that ban North Korea from developing ballistic missile and nuclear weapons technology.
Dr Kim Dong Yup, an analyst at the Institute for Far Eastern Studies at Kyungnam University in Seoul, said the range of the missiles meant they were probably fired as a threat to Japan.
"Timing-wise, the missile launches can be best connected to the G-20," he said. "They are trying to show their confidence by launching missiles right next to where everyone is looking."
Japanese Prime Minister Shinzo Abe approached South Korean President Park Geun Hye at the G-20 shortly after the news of the launches, and the two leaders agreed to work together closely to counter the provocation, Japan's Foreign Ministry said in a statement.
The firings also came shortly after Ms Park met Chinese President Xi Jinping, when she called North Korea's provocations a challenge to relations between the two countries.
Relations between Seoul and Beijing have cooled since South Korea announced plans to deploy a US anti-missile defence system on the peninsula.
Seoul has argued the Terminal High Altitude Area Defence (Thaad) is necessary to counter growing North Korean threat. Beijing has called the system a threat to regional security because its radar can see beyond North Korea.