North Korea's leaders are promising more offensive military actions in light of moves by the United States, South Korea and other allies to strengthen security ties.
Washington and Seoul updated their bilateral deterrence strategy on Monday to more effectively counter the North's nuclear and missile threats.
The United States and South Korea are also working with Japan on a mechanism for sharing real-time data on Pyongyang's launches. They plan to have it ready by year-end.
A defense ministry spokesperson in the North released a statement on Thursday referring to "hostile forces." It says their military posturing is not defensive, but aimed at invading North Korea.
The statement vows to "strongly control" all threats to national security with "offensive and overwhelming counteraction capabilities and through visible strategic deterrent military actions."
On Wednesday, the North announced it had successfully conducted ground tests of an engine for a new intermediate-range ballistic missile that uses solid fuel.
And earlier this month, officials in Pyongyang designated November 18 as "missile industry day" to mark the successful test of a new ICBM last year.