South Korea has sent 1 billion won ($893,239.96) worth of sanctioned material to North Korea, customs data showed on Friday, raising concern ties with the United States could be damaged as the South pursues cooperation with the North.
The United States is pressing North Korea to give up its nuclear weapons program, calling for stringent implementation of tough U.S. and U.N. sanctions.
But at the same time, its ally, South Korea, is trying to increase cooperation with its old rival.