North Korea says it has no plans to conduct a nuclear test, despite what it says are South Korean attempts to provoke one.
The North Korean foreign ministry made the announcement Saturday, saying South Korea is trying to drum up an excuse to increase sanctions on the impoverished North.
Satellite photos taken in April show activity at North Korean nuclear sites, and Pyongyang attempted a test launch of a long-range rocket that month.
North Korea said the rocket was to put a satellite into orbit, but Western powers said it was a missile test that violated a United Nations ban on testing such technology.
South Korea's joint chiefs of staff Thursday said it is "closely paying attention to North Korean movements" after a significant number of sorties by North Korean jets near South Korean airspace in the past several weeks.
Some information for this report was provided by AP, AFP and Reuters.