Latest comments come as US and South Korea hold joint military exercises involving thousands of troops.
North Korean leader Kim Jong Un has ordered heightened readiness for war after inspecting troops at a major military operations base in the country’s west.
The state-run Korean Central News Agency (KCNA) did not reveal the location of the base in its report on Thursday.
The North Korean leader said the military must “dynamically usher in a new heyday of intensifying the war preparations in line with the requirements of the prevailing situation”, according to KCNA.
“Our army should … steadily intensify the actual war drills aimed at rapidly improving its combat capabilities for perfect war preparedness,” he added.
Kim’s visit took place as forces from the United States and South Korea continued their annual Freedom Shield large-scale military exercises.
The drills, expected to involve 48 field exercises including missile interception drills, bombing, air assault and live-firing, began on Monday with twice the number of troops participating compared with last year.
North Korea has long condemned military drills by the US and South Korea, claiming they are rehearsals for an invasion, and has conducted weapons tests in response to previous exercises.
On Monday, KCNA quoted an unnamed spokesperson for North Korea’s Ministry of Defence urging Seoul and Washington to cease their “reckless” and “frantic war drills”.
The US and South Korea “will be made to pay a dear price for their false choice”, the spokesperson added.
In Thursday’s report, KCNA did not mention whether Kim directly referred to the Freedom Shield drills.
It said the troops at the base were conducting manoeuvres under conditions simulating actual war.
North Korea has continued to carry out missile tests this year as it modernises its military.