US officials confirmed Sunday's test, a day before the opening of the nuclear Non-Proliferation Treaty conference in New York, and called on its allies to express concern.

But they said they were not surprised by incident, the latest short-range missile test apparently timed for political impact.

"We're not surprised by this. The North Koreans have tested their missiles before. They've had some failures," White House Chief of Staff Andrew Card told CNN television.

"We have to work together with our allies around the world -- especially the Japanese, the South Koreans, the Russians and the Chinese -- to demonstrate that North Korea's actions are inappropriate," Card said.

"We don't want them to have any nuclear weapons, we don't want the Korean peninsula to have any nuclear weapons on it."

Japan, which neighbours North Korea and like the US is also involved in the six-nation process of trying to disarm the self-avowed nuclear power, said it was treating the test as a "domestic" drill.