North Korea threatened Tuesday to use nuclear weapons against the United States as it announced that it has restarted operation of its nuclear reactor at Yongbyon complex, Yonhap news agency reported.

North Korea has made constant "innovations" in its capacity for nuclear deterrence "by steadily improving the levels of nuclear weapons with various missions in quality and quantity," the director of the Atomic Energy Institute said in a comment carried by the North's official Korean Central News Agency.

It said all the nuclear facilities in Yongbyon including the uranium enrichment plant and 5 megawatt reactor were rearranged, changed or readjusted and they started normal operation.

The unidentified director also warned that North Korea is fully ready to deal with the United States and other countries Pyongyang claims are hostile toward North Korea "with nuclear weapons any time."

The North's threat is likely to dampen South and North Korea's hard-won conciliatory mood on the peninsula following their landmark deal on easing military tension in late August.

On Monday, North Korea hinted at launching what it calls "a series of satellites around the North's 70th anniversary of the founding of the Workers' Party of Korea (WPK), which falls on Oct. 10.

North Korea's nuclear and missile tests have flared up tension on the Korean Peninsula amid concerns that it may soon develop the technology to mount a nuclear warhead on long-range ballistic missiles capable of reaching the U.S. mainland.

The North has said it has already made nuclear warheads small enough to fit on a missile as it has claimed the success of test-firing a submarine-launched ballistic missile (SLBM) in May.

Source: MENA