|US Secretary of State John Kerry(Yonhap)|
The meeting came as the two countries have been struggling to narrow differences in negotiations to put together a new package of UN Security Council sanctions aimed at punishing the North for its September nuclear test.
The main point of contention in the negotiations is the US demand for banning all of North Korea's exports of coal, a key source of hard currency for the communist regime, including exports for "livelihood purposes."
The latest UN sanctions, adopted in March in response to the North's fourth nuclear test in January, ban the North's exports of coal, but those sanctions are not applied in case of exports for "livelihood purposes."
Closing the loophole is the main US goal in the sanctions talks, but China has balked at it. (Yonhap)