The United States said Monday that a new United Nations report "clearly and unequivocally documents the brutal reality" of North Korea's human rights abuses.

Washington strongly welcomes and supports the report, "which provides compelling evidence of widespread, systematic, and grave human rights violations" by the reclusive regime, State Department deputy spokeswoman Marie Harf said.

North Korea's leaders should be brought before an international court for a litany of crimes against humanity that include exterminating, starving and enslaving its population, a U.N. team said Monday.

A hard-hitting report on the nuclear-armed totalitarian state also strongly criticized its denial of basic freedoms of thought, expression and religion, and its abduction of citizens of neighboring South Korea and Japan.

China's vice foreign minister is visiting North Korea, the ministry said Monday, making him Beijing's most senior envoy known to go to Pyongyang since its young leader executed his uncle, a key China interlocutor.

The late Jang Song-Thaek was North Korea's second most powerful figure, and provided a valuable link between the two countries before being purged in December following a sidelining of other core leaders.

A South Korean court on Monday sentenced an opposition legislator to 12 years in prison after a rare treason trial saw him convicted of plotting an armed revolt in support of North Korea.

Prosecutors had demanded 20 years for Lee Seok-Ki, 52, who was tried along with six other members of his left-wing United Progressive Party.

North Korea celebrated the birth anniversary of late leader Kim Jong-Il Sunday after promoting key military officials including the chief of its rocket unit, state media said.

Kim Rak-Gyom, the commander of the Korean People's Army (KPA) Strategic Rocket Force Command, was promoted to colonel general at the order of leader Kim Jong-Un, the Korean Central News Agency (KCNA) reported late Saturday.

Recent satellite imagery suggests North Korea has stepped up excavation work at its main nuclear test site, but there are no signs of an imminent test, a U.S. think-tank said Friday.

The images indicate a "significant acceleration in excavation activity" at the remote Punggye-ri test site in the northeast, said the closely-followed 38 North website of the Johns Hopkins University's U.S.-Korea Institute.

U.S. Secretary of State John Kerry met Chinese President Xi Jinping Friday, amid increasingly tense territorial rows between Beijing and Washington's security allies Tokyo and Manila.

Kerry started his Valentine's Day visit with a meeting with Xi at the Great Hall of the People, and was due to meet other officials including Chinese Foreign Minister Wang Yi later.

High-level talks between the rival Koreas ended Friday with a rare agreement to go ahead as planned with a reunion for divided families, despite the North's objections to overlapping South Korea-U.S. military drills.

The two sides also agreed to stop exchanging verbal insults and to continue their nascent dialogue at a convenient date, according to a joint statement read to reporters in Seoul by South Korea's chief talks delegate Kim Kyou-Hyun.

U.S. Secretary of State John Kerry Thursday called on key Asian allies South Korea and Japan to improve their deeply strained relations and work together for regional stability.

"It's up to Japan and the Republic of Korea to put history behind them," Kerry told a joint press conference after talks with his South Korean counterpart Yun Byung-Se.

North and South Korean officials sat down to their highest level talks for years Wednesday, seeking an upswing in ties despite a bitter row over looming South Korea-U.S. military exercises

The discussions in the border truce village of Panmunjom had no fixed agenda, but aimed to cover a range of "major" issues, including a planned February 20-25 reunion for family members divided by the Korean War.