In what may be a sign of deteriorating relations between the two countries, North and South Korea traded artillery shots on Wednesday. The exchange was seemingly prompted by the North Korean military’s firing of artillery shells into the water near its border with South Korea, which officials from the North defended as a military exercise. South Korean troops fired warning shots into the air in response. Still, while the bellicose military posturing is worrying, progress appears to be looming on economic and humanitarian issues between the two Koreas. High-level diplomatic talks, which are part of North Korea’s bid to secure economic help, are ongoing, and South Korean officials say the latest spat between the neighbours wouldn’t throw those talks into jeopardy.