South Korea says six-party talks at risk if North conducts new nuclear test
In March, the North warned it would not rule out a "new form" of nuclear test to boost its nuclear deterrent, after the U.N. Security Council condemned Pyongyang's launch of a mid-range ballistic missile into the sea east of the peninsula.
The six-party talks, joining the United States, Russia, China, the two Koreas and Japan, have been stalled for years.
(Writing by Nick Macfie)