(CNN) -- Dennis Rodman's latest round of controversial "basketball diplomacy" in a country ruled by one of the world's most repressive regimes is about to begin.
The former NBA star and a documentary crew are due to fly Thursday afternoon from China to North Korea, where he is to spend four days helping train a team of North Korean basketball players for a January exhibition in Pyongyang.
That January 8 exhibition -- said to be against a yet-unannounced team of former NBA players -- will celebrate the birthday of North Korean leader Kim Jong Un, whom Rodman has called a friend and a "very good guy" despite international condemnation of the country's human rights records.
Rodman's trip -- sponsored by the online betting company Paddy Power -- is the 52-year-old's third to North Korea.
Rodman said he struck a friendship with Kim, a basketball fan, during Rodman's first trip in February. After the two men sat next to each other watching a basketball exhibition in North Korea's capital, Rodman told Kim that "you have a friend for life."
Rory Scott, a Paddy Power spokesman, said earlier this month that December's trip is nonpolitical, but is intended "to prove once again that sport has the power to rise above all issues."
It's not clear whether Rodman will meet with Kim during the basketball training visit.
The trip comes at a time of political turmoil in the secretive nuclear-armed nation, ongoing tensions between North Korea and the United States and outcries over North Korea's human rights record.
Tensions in the region were ratcheted up as North Korea carried out a long-range rocket launch a year ago and an underground nuclear test, its third so far, in February. The U.N. sanctions that followed were met by a barrage of threatening rhetoric from Pyongyang.
Rodman was criticized over his first trip in part because it came during this period, in which North Korea was threatening missile strikes on the United States, South Korea and Japan.
The situation has calmed since. But in a sign of internal political upheaval, North Korea announced last week that the regime had executed Kim's uncle, Jang Song Thaek, who had been regarded as the country's second-most powerful figure. North Korea's official news agency accused him of trying to overthrow the state.
Rodman is "really important" to the North Korean regime, said North Korea expert and Forbes.com columnist Gordon Chang.
"Got to remember that Kim Jong Un needs to show that his regime, his government, is united, which it isn't," said Chang, author of "Nuclear Showdown: North Korea Takes On the World."
"With Dennis Rodman, we're going to see a lot of made-for-television events. Everybody's going to be smiling, everything will appear normal, and this will bolster the regime," Chang told CNN Newsroom on Wednesday.
'It is not my job to talk about' detained American
The United States has other points of contention with North Korea, including the detention of Korean-American Kenneth Bae.
Bae, arrested in North Korea in November 2012, was sentenced to 15 years of hard labor after he was found guilty of "hostile acts" and attempts to topple the government through religious activities.
U.S. officials have repeatedly called on North Korean officials to release Bae, widely reported to be a Christian missionary, on humanitarian grounds. His family has said he suffers from chronic health conditions that require doctors' care.
Is Dennis Rodman smart on North Korea?
Earlier this year, Rodman made no secret about his desire to help Bae. He tweeted that he wanted Kim to "do him a solid" by freeing the American prisoner.
But after his second trip to see Kim in September, Rodman told reporters that it was "not my job to talk about Kenneth Bae."
"Ask Obama about that, ask Hillary Clinton about that," Rodman said. "Ask those ---holes."
Bae's sister, Terri Chung, told CNN on Wednesday that she wants Rodman to press for her brother's freedom.
"I would certainly hope and plead with Mr. Rodman to reconsider and ... make the case" for Bae's freedom, she said.
Rodman, the tattooed and pierced NBA retiree, has emphasized that he's not an official diplomat between the United States and North Korea.
"It's about trying to open Obama's and everyone's minds," he said in September while announcing the January exhibition, aiming some of his remarks at the U.S. president. "You don't have to talk about politics. ... Meet him or even give him a call. That's all he wants."
Paddy Power has said Rodman's team of former NBA players would be announced sometime this month.o
CNN's Steve Forrest, Holly Yan, Jethro Mullen, Josh Levs and Brooke Baldwin contributed to this report