Relations between North and South Korea have taken a turn for the worse as North Korea denounced the US and South Korea for a joint military exercise that began on Tuesday. A senior North Korean official said “They must be made to clearly understand how dearly they have to pay for answering our good faith with hostile acts after letting go the opportunity for improved inter-Korean relations.” The relationship between the two neighboring countries had just begun to improve as a line of communication had been reopened last month. North Korea, however, stopped answering this hotline on Tuesday, prior to the official’s warnings. The collaborative military exercises are an annual event for the two countries and are “purely defensive in nature” according to the US State Department.