North Korea fired a suspected ballistic missile off its east coast into the sea on Wednesday, South Korean and Japanese authorities said. The launch is the first since Oct. 19, when the North tested a new submarine-launched ballistic missile. It comes just days after the country’s leader Kim Jong Un insisted in a New Year’s policy speech he would continue to bolster its defense power, pursuing high-tech weapons to counter what he called military instability on the Korean peninsula. Wednesday’s launch, which violated of multiple U.N. Security Council resolutions banning the country from ballistic and nuclear weapons tests, is estimated to have flown just over 310 miles. Japan’s prime minister called it “very regrettable,” and promised to strengthen surveillance. In a statement, South Korea’s Joint Chiefs of Staff said South Korean and U.S. analysts would closely monitor the situation for further detail.