China's human rights record worsened in 2012 amid an increasingly harsh crackdown on Tibetan and Uighur areas, the United States warned Friday in an annual report.

"The human rights environment in China continued to deteriorate in 2012," the State Department said in its human rights report.

It highlighted "a crackdown on human rights activists, increasingly harsh repression in ethnic Tibetan and Uighur areas" and growing online censorship.

"Individuals and members of groups seen as politically sensitive by the authorities continued to face tight restrictions on their freedom to assemble, practice religion, and travel," the report said.

And it denounced the use of "enforced disappearance, soft detention and strict house arrest" to stifle dissent.

Secretary of State John Kerry, who traveled to Beijing over the weekend, raised specific cases during his talks with Chinese leaders, including Chen Kegui, the nephew of blind self-taught lawyer Chen Guangcheng.

Chen Guangcheng infuriated Beijing authorities by exposing forced abortions, and dramatically escaped house arrest in April 2012 by scaling the walls of his home and taking a getaway car to the US embassy.

His nephew was jailed for three years in November for attacking officials who descended on his village after the dissident fled to the US embassy.

The US report also highlighted the "deplorable" conditions in North Korea, where defectors "continued to report extrajudicial killings, disappearances, arbitrary detention, arrests of political prisoners, and torture."

And it denounced the North's "vast network of political prison camps, in which conditions were harsh and life-threatening."

But there was praise for Myanmar, also known by its former name of Burma, where military leaders have brought in some lightning democratic reforms.

"Since 2011 the government has released more than 700 political prisoners, many of whom had been imprisoned for more than a decade," the report said, as it noted the free and fair by-elections in April in which long-time opposition leader Aung San Suu Kyi was elected to parliament.

"However, Burma's transition is not yet complete," it warned, adding a lot of work will be "essential" to ensure free and fair national elections in 2015.

"Many elements of the country's authoritarian structure -- repressive laws, pervasive security apparatus, corrupt judiciary, restrictions on freedom of religion and dominance of the military -- remain largely intact," it said.

Human trafficking remained an issue of great concern, and urgent work was needed to overcome ethnic tensions wracking Kachin and Rakhine states.

"It will require government action to protect the human rights of all individuals in Burma, and it will require real leadership from influential religious, political, and community figures," the report said.

Kerry also praised Myanmar's progress, saying that "the Burmese government has opened the doors to a stronger partnership with our neighborhood and with countries around the world."

"Has it reached where we want it to be? But it's on the road. It's moving," he told journalists in unveiling the 2012 report.

The report concluded that "ultimately, Burma's future will be determined by the Burmese people, but its democratic transition, if successful and fully implemented, could serve as an example for other closed societies."

Vietnam was also singled out for criticism, with the report saying that human rights had deteriorated there in 2012.

"Authorities restricted freedom of expression, imprisoned dissidents using vague national security legislation, harassed activists and their families, and disregarded the rule of law," it said.