North Korean state media on Wednesday accused the United States of planning an attack under the cover of talks now under way in Beijing.
"The United States is trying to pull a dirty business against the DPRK (North Korea) behind the curtain of talks," wrote an analyst in the ruling communist party newspaper Rodong Sinmun.
"This is clear proof that it is seeking to vanquish the DPRK with a military strong arm, whetting its sword of aggression under the mask of dialogue."
The article, carried by the official Korean Central News Agency, took exception to a plan known as Conplan 5029.
The Washington Post in October reported that the plan was drawn up by the US and South Korea following North Korea's nuclear test earlier that month.
It said Conplan 5029 focuses on preemptive action to thwart North Korean moves involving potential export of weapons of mass destruction.
It would be the first joint US-South Korean plan to take action against North Korea even if the North does not invade or attack the South first, the Post said.
"Watching the acts of the US bellicose forces framing war plots against the DPRK behind the scene while holding dialogue under the public eyes, the DPRK is getting further convinced that the United States is a dangerous one," the North's commentary said, without specifically referring to the six-nation talks.
The talks, which resumed Monday after a 13-month break, aim to persuade the North to abandon its nuclear programmes in return for economic benefits and security guarantees.