Analysts say the recent North Korean threats were partly an attempt to push Washington to agree to disarmament-for-aid talks.
In response to Saturday's missile test, the US said threats or provocations will only further isolate North Korea from the rest of the world and undermine international efforts to bring peace and stability to Northeast Asia.
"We continue to urge the North Korean leadership to heed President Obama's call to choose the path of peace and come into compliance with its international obligations," said National Security Council spokeswoman Caitlin Hayden.
This past week, Glyn Davies, the top US envoy on North Korea, ended trips to South Korea, China and Japan. On Friday, an adviser to Japanese Prime Minister Shinzo Abe returned from North Korea but didn't immediately give details of his talks with officials there.
On Monday, North Korean state media showed that the country's hard-line defence minister had been replaced by a little-known army general. Outside analysts said it was part of leader Kim Jong Un's efforts to tighten his grip on the powerful military after his father Kim Jong Il died in December 2011.
The United States and Japan are participants in six-nation nuclear disarmament talks along with the Koreas, Russia and China. North Korea walked out of the talks in 2009 after the United Nations condemned it for a long-range rocket launch.
North Korea possesses an array of missiles. US and South Korean officials do not believe the North's claim that it has developed nuclear warheads small enough to place on a missile. Last week in Washington, South Korean President Park Geun-hye and President Barack Obama warned North Korea against further nuclear provocations.
Tension between the two Koreas remains high after both sides pulled out their workers from a jointly run factory complex earlier this year. The countries remain technically at war after the 1950-53 Korean War ended in a truce instead of a peace treaty.
- AP