The North Korean leader said the partnership poses a grave threat to his country and vowed to further bolster his nuclear weapons program.

SEOUL (Reuters) -North Korean leader Kim Jong Un criticised trilateral military cooperation among the United States, Japan and South Korea for raising tensions in the region and vowed countermeasures,

The warning came after Kim accused the US of escalating tensions on the Korean Peninsula through its alliance with South Korea and Japan. View on euronews

The first tour is set to take place Feb. 12 to 18, when major celebrations are planned for the birthday of the country's late leader Kim Jong Il, one of North Korea's biggest holidays.

North Korean leader Kim Jong Un has vowed to bolster his nuclear weapons program in response to the U.S.’s enhanced security partnership with South Korea and Japan. Last year, the U.S. expanded bilateral military exercises with South Korean and trilateral training with South Korea and Japan.

North Korea has vowed to keep developing nuclear weapons in response to U.S. cooperation with South Korea and Japan.