North Korea on Thursday reiterated its stance that its nuclear capability is the outcome of what it claims is nuclear blackmail from Washington, and threatened to launch a nuclear attack on the U.S. mainland.

The Korean Central News Agency (KCNA), Pyongyang's official news outlet, said the U.S.'s call for a "world without nuclear weapons" is a prelude to a nuclear war against the communist state.

"The 4th Nuclear Security Summit held in the U.S. was an extremely deceptive and provocative farce aimed to persist in its nuclear high-handed and arbitrary practices," the KCNA said.

The North claimed that during the nuclear security summit last week, the U.S. forced its allies into boosting the atmosphere of "sanctions" and pressure on Pyongyang by saying the communist state's nuclear threat is the greatest problem facing the international community.

"If the U.S. shows even the slightest sign of provoking a nuclear war of aggression, we will make a merciless nuclear strike at the U.S. mainland. The nuclear force of the DPRK is the one of justice for ending the U.S. nuclear crimes," the report said.

DPRK is the acronym of the North's official name, the Democratic People's Republic of Korea.

During a meeting with U.S. President Barack Obama and Japanese Prime Minister Shinzo Abe in Washington last week, South Korean President Park Geun-hye warned North Korea against staging another provocation.

North Korea is under growing international pressure to drop its nuclear ambitions after it carried out its fourth nuclear test on Jan. 6 and a long-range rocket launch on Feb. 7.

The U.N. Security Council has imposed the toughest-ever sanctions on North Korea that call for, among other things, the mandatory inspection of all cargo going into and out of the North and a ban on the country's exports of coal and other mineral resources to cut off North Korea's access to hard currency. (Yonhap)