The launches of four banned ballistic missiles by North Korea were training for an attack on a U.S. base in Japan, state media says.

North Korean news agency KCNA said the launches were an exercise designed to prepare the country for a strike.

Supreme Leader Kim Jong-Un had overseen the launch, the agency said, and had lauded what he had witnessed.

KCNA said the exercise was carried out by an artillery unit "tasked to strike the bases of the U.S. imperialist aggressor forces in Japan in contingency".

The four missiles flew an average of 620 miles and reached an altitude of 160 miles, Japan's Defence Minister Tomomi Inada said.

Some landed as close as 190 miles from Japan's northwest coast.

Under U.N. resolutions, Pyongyang is banned from using ballistic missile technology.

Washington and Tokyo have called for the United Nations Security Council to meet over the launches, which is expected to take place on Wednesday.

President Trump has previously said he will not allow the North to obtain a nuclear weapon that could threaten the U.S.

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