But Joseph Dunford, chairman of the US Joint Chiefs of Staff, said last week that the military exercises were "not now on the table as part of the negotiation at any level" and the Ulchi-Freedom Guardian (UFG) exercises were going ahead as planned.
The US and South Korea hold two sets of war games every year, involving a massive number of troops and military hardware.
State media in the North said: "The joint exercise is the most explicit expression of hostility against us, and no one can guarantee that the exercise won't evolve into actual fighting".
Analysts have said all eyes will be on the war game that could send tensions spiralling back upwards after the war of words between the U.S. and North Korea appeared to have cooled off slightly.
"The US should pay heed to the statement of the DPRK government that we would not rule out the use of any final means", warned another article.
The 10-day joint military exercise with South Korea has been condemned by Pyongyang as "reckless behaviour driving the situation into the uncontrollable phase of a nuclear war". North Korea has long denounced the drills as a war rehearsal for a northern invasion, reports Yonhap News Agency.
Some experts say North Korea is mainly focused on the bigger picture of testing its bargaining power against the United States with its new long-range missiles and likely has no interest in letting things get too tense during the drills. North Korea on the other hand wants the U.S.to drop its hostile policies before agreeing to talks. The situation has been calmer in the recent days, with Pyongyang facing sanctions from their biggest ally, China. This has led to speculation about whether the exercise itself has been scaled down.
Joint Chiefs chairman General Joseph Dunford in Seoul.
The exercise will bring together as many as 50,000 South Korean soldiers and approximately 17,500 USA service members for a computer simulation of war on the Korean Peninsula.
US forces will join military forces from major South Korean units representing all services, as well as South Korean government participants.
No field training like live-fire exercise or tank maneuvering is involved in the Ulchi drills, in which alliance soldiers, mostly senior officers, sit at computers to practice how they engage in battles and hone their decision-making capabilities.
Just last week, Pyongyang said it had finalized a plan to fire four missiles toward the U.S. territory of Guam. USA and Korean marines participated in the exercise along with soldiers from Australia and New Zealand under the United Nations command.
Nuclear tensions are high again between North Korea and the United States - days after a much-welcomed cooling-off period - with renewed sabre-rattling calling out President Trump by name as the US and South Korea launch joint military maneuvers today.