"If his parents choose to address it [his health], they are more than welcome to do so", she said.
The uncertainty over Warmbier's condition and treatment in detention speaks to the opacity of North Korea's justice system. Two ambulances met the plane on the runway to transfer Otto to the hospital.
During his 18-month incarceration, the Warmbiers have only heard from Otto once - through a letter on March 2, 2016. They say North Koreans told US authorities that their son contracted botulism and never awoke after he was given a sleeping pill.
A senior Trump administration official told Fox News Rodman was going to the North "as a private citizen".
Quickly, that elation turned to dread as details emerged and Simons learned of the coma. She struggled Tuesday night to find the words.
A police officer stood guard nearby.
Dennis Rodman, the former National Basketball Association bad boy who has palled around with North Korean leader Kim Jong Un, flew to Pyongyang on Tuesday on a trip he says he hopes will "open a door" for his former "Celebrity Apprentice" boss - U.S. President Donald Trump.
She tells reporters, "we are grateful and thankful" for Warmbier's release, but says it is "too soon" to talk about dialogue between the USA and North Korea. Yun and an American delegation traveled to Pyongyang on June 12 and demanded to visit Warmbier and his release on humanitarian grounds.
But State Department spokeswoman Heather Nauert said the visit "had nothing to do with the release".
"In no uncertain terms North Korea must explain the causes of his coma", Richardson, whose Center for Global Engagement had directly sought Warmbier's release with the North Korean government, said in a statement.
"On whether these two incidents are related, one should directly ask the country concerned", he said during a regular press briefing.
Mr Tillerson said the Department of State was continuing "to have discussions" with North Korea about the release of other three American citizens imprisoned there.
The White House says securing the release of an American college student from a North Korean prison "was a big priority" for President Donald Trump.
"The visit was the first time the United States was able to confirm Warmbier's status after he was sentenced", Fox News reported. His family were told that he contracted botulism after the trial, and was given a sleeping pill from which he never awoke. "And why was this not disclosed?" He is on medevac flight on his way home. He said that over the past 18 months, Warmbier's family has "had to endure more than any family should have to bear".
"I want my kid home".
Warmbier was supposed to graduate from the University of Virginia in May.
Meanwhile, the ministry said that it has approved three more requests by local civic groups to contact North Koreans, raising the total to 21.
President Trump then promptly put into motion the process enabling Warmbier's safe return to his family in Ohio.
Joseph Yun, the US special envoy on North Korea, met with North Korean officials in Oslo, Norway, in May and reached an agreement for Swedish diplomats to visit Warmbier.
Republican Senator Rob Portman says North Korea should be "universally condemned for its abhorrent behavior".
The 22-year-old's return marks an end to the ordeal that his family has been through, not knowing what had happened to Warmbier since he was sentenced to 15 years in prison with hard labor in March last year. His parents said that University of Virginia students had been on a tour of the reclusive country.
Warmbier was detained in January 2016 and sentenced to 15 years of hard labour in March 2016 for trying to steal an item with a propaganda slogan, according to North Korean media.