"A really good trip", Dennis Rodman said upon his return.
When it works, "it's a brilliant propaganda coup", for the regime, he said.
The contact began with back channels more than a year ago, the US has no official diplomatic relationship with North Korea.
Otto Warmbier is in stable condition but has a severe neurological injury, University of Cincinnati Medical Center officials said at a Thursday morning press conference. The U.S. wouldn't publicly describe their condition.
When Danny Gratton met Otto Warmbier in Beijing in late December 2015, they were on their first day of a tour to North Korea that only one of them would successfully complete.
"It must have been an accident and that's probably why they were hiding it for a year", said Go Myong-hyun, researcher at the Asan Institute for Policy Studies.
"I am very impressed with the humanitarian relationship of the Korean government to serious criminals like me", the student said in a statement that the television reported.
Warmbier fell into a coma while serving his sentence.
"This is not a very good situation to try to improve the relations with North Korea, when they treat our people like this", he added, reminding three other political prisoners remain there.
Richardson said he is now urging the Trump White House to make sure the USA government pays for Warmbier's care and ensures he has access to the nation's best doctors.
During the time of his visit, Rodman said to have played basketball with the North Korean men's and women's teams, visited the city zoo, met Olympic athletes and presented the country's sports minister with a copy of President Donald Trump's book, "The Art of the Deal".
Rodman has a controversial history on the subject of Americans detained in North Korea. The North Koreans agreed to let Swedish diplomats visit the US detainees, including Warmbier.
Yun met with the North Korean ambassador to the U.N.in NY on June 6 and was told of Warmbier's medical status.
Flamboyant former National Basketball Association star Dennis Rodman landed in Beijing Saturday after a visit to North Korea, describing the escapade as a "real good trip".
"It is not good if you go back and start selling stories about suffering and torture as that will damage North Korea's worldwide standing", he said.
"Pyongyang timed the release to deliver a message to Washington". They didn't tell us in our meetings with the North Koreans in NY, 20 times in the previous year.
He said that the rare exchanges might be the beginning of "a diplomatic dance" that could lead to talks.