U.S. officials say North Korea has test fired at least six missiles, including a long-range missile that failed shortly after launch. High level consultations are underway.

White House officials call the series of launches a provocation, but add there is no immediate threat to the United States.

All the tests occurred early Wednesday morning local time within the span of hours. Most involved short to medium range missiles that landed in the Sea of Japan. But one, the failed missile, was a Taepodong 2, the intercontinental missile that has been a focus of international attention.

The White House responded to the news of the launches with caution and relative calm. Spokesman Tony Snow said North Korea has further isolated itself by rebuffing diplomatic efforts and defying neighbors who asked them not to launch. National Security Advisor Steve Hadley said the North Koreans have now broken their own moratorium on testing, which was adopted in 1999.

When asked what action the United States might take, now that North Korea has defied calls from the international community to refrain from long range missile testing, both officials put the focus on diplomacy. Snow announced the administration's chief negotiator on North Korea - Assistant Secretary of State Christopher Hill - will travel to the region later Wednesday. At the same time, Hadley will meet with his South Korean counterpart in Washington.

Hadley told reporters President Bush was notified almost immediately once the launches were detected. He said the president was not very surprised that North Korea would defy the international community. He said it is hard to understand why they would do it, and stressed it is important now to be able to assess their true intentions.

For his part, the White House spokesman downplayed the notion the launches were timed to coincide with America's Independence Day holiday. When asked by reporters about the timing Tony Snow referred to the North Korean leader and said simply ask Kim Jong-Il.