North Korea has angrily denied a report that its ruler used Adolf Hitler's memoir as a leadership guide, threatening to kill the authors of the report.

The article by New Focus International, an online news portal run by North Korean defectors, said Kim Jong-Un had given copies of "Mein Kampf" to his top officials, urging them to study it as a leadership skills manual.

United Nations Secretary-General Ban Ki-moon arrived in Beijing on Tuesday for high-level talks with Chinese officials on North Korea, Syria and other issues, his spokesman said.

Ban will meet with Chinese President Xi Jinping, Premier Li Keqiang and senior foreign policy officials during his stay, spokesman Martin Nesirky said.

North Korea, one of the world's most repressive societies, branded the United States a "kingpin" of human rights abuses Tuesday, following revelations of the U.S. government's Internet surveillance program.

A bylined commentary in the government's official Minju Joson newspaper said U.S. National Security Agency whistleblower Edward Snowden had exposed the global nature of the NSA's intrusive monitoring activities.

South Korea's top envoy on North Korea left Tuesday for a meeting in Washington with his U.S. and Japanese counterparts, two days after Pyongyang proposed direct, high-level talks with the United States.

After Washington, Cho Tae-Yong will travel on to Beijing -- where he is likely to overlap with a visit by North Korea's chief nuclear negotiator, Kim Kye-Gwan, to the Chinese capital.

South Korea on Monday joined the United States in insisting that rival North Korea take "concrete" steps towards abandoning its nuclear weapons if it genuinely wants to end its international isolation.

The South's comment came a day after Pyongyang sought to circumvent Seoul by proposing direct talks with Washington.

The United States on Sunday welcomed North Korea's proposal for high-level negotiations but said it must first curb its nuclear program and would not be able to talk its way out of global sanctions.

White House Chief of Staff Denis McDonough said negotiations have always been the administration's "preferred outcome" but that such talks would have to be "real" and "based on them living up to their obligations."

North Korea on Sunday proposed high-level talks with the U.S. on denuclearization and easing tensions on the Korean peninsula, just days after it abruptly canceled a rare meeting with the South.

Tension has been high on the peninsula since the North's third nuclear test in February that triggered new U.N. sanctions which ignited an angry response from Pyongyang, including threats of nuclear attacks on Seoul and Washington.

North Korea on Saturday made a fresh vow to build up its nuclear deterrent in the face of "threats of war" from the United States and a "policy of confrontation" from the South.

An editorial in Pyongyang's ruling party daily, the Rodong Sinmun, said "reckless" war exercises by the U.S. and South Korea could spark a nuclear war at any moment.

North Korea on Thursday blamed South Korean arrogance and deceit for the collapse of planned talks between the two rivals and warned that prospects for any future dialogue had been severely damaged.

The two Koreas had initially agreed to hold their first high-level talks in six years in Seoul on Wednesday and Thursday this week, but they were called off at the last minute following a dispute over protocol.

South Korea rejected any blame Wednesday for the collapse of planned talks with the North, as businessmen from a closed joint industrial zone complained they were being ruined by politics.

North Korea, meanwhile, offered no comment at all on the last-minute cancellation of the dialogue, and refused to answer routine calls from South on a newly-restored inter-government hotline.