Suffering from severe brain damage, he died Monday in his hometown of Cincinnati, Ohio, surrounded by family who decried his "awful torturous mistreatment" at the hands of Pyongyang, while taking solace in the fact he made it home before he died.
Warmbier was on a tourist trip when he was arrested and handed a 15-year sentence in March last year, a punishment US officials decried as out of proportion to his alleged crime.
"It's a total disgrace what happened to Otto," Trump said during an event in the Oval Office. "It should never, ever, be allowed to happen. And frankly if he were brought home sooner, I think the result would have been a lot different."
The young man's father, Fred Warmbier, previously criticized former president Barack Obama's administration for how little he did for their son, saying officials had counseled the family against speaking out to avoid antagonizing the North Korean regime.
"The results speak for themselves," the student's father said last week.
Trump paid tribute to Warmbier's family, with whom he has spoken personally, saying "it's incredible what they have gone through."
- 'Heavy responsibility' -
A day earlier, the president slammed the "brutal regime" in Pyongyang, and said he was determined to "prevent such tragedies from befalling innocent people at the hands of regimes that do not respect the rule of law or basic human decency."
Trump's stern language was echoed by South Korean President Moon Jae-In, who said in an interview ahead of a White House visit next week that North Korea bears responsibility for the student's death.
"We cannot know for sure that North Korea killed Mr Warmbier, but I believe it is quite clear that they have a heavy responsibility in the process that led to his death," Moon told CBS television's "This Morning."
Warmbier's release came amid mounting tensions following a series of missile tests by Pyongyang, in an arms buildup that Washington has dubbed "a clear and present danger to all."
Moon, a center-left politician sworn in last month after a landslide win, favors engagement with the North to bring it to the negotiating table, rather than the hardline stance of his ousted predecessor.
Asked how the Warmbier case would affect his efforts to engage North Korea, Moon added: "I believe we must now have the perception that North Korea is an irrational regime.
"Working with such a country, we must achieve the goal of the complete dismantlement of North Korea's nuclear program."
- 'He was home' -
Kim Jong-Un's regime claimed that Warmbier contracted botulism and fell into a coma soon after being sentenced last year.
Doctors last week said Warmbier had suffered severe neurological injuries, for which tests did not conclusively reveal the cause.
They said Warmbier's condition was probably caused by cardiopulmonary arrest cutting the blood supply to the brain.
The young man was described as being in a state of "unresponsive wakefulness," opening his eyes but showing no signs of understanding language or of being aware of his surroundings.
His family said Monday that he first appeared anguished when he first arrived home, but died "at peace."
"He was home and we believe he could sense that," they added.
The young man's funeral will take place at 9 am (1300 GMT) on Thursday at a high school in Cincinnati, and will be open to the public.
- Risk 'too high' -
US Secretary of State Rex Tillerson warned Monday that Washington holds North Korea "accountable" for Warmbier's fate, and demanded the release of three other Americans held by North Korea.
Two were teachers at a Pyongyang university funded by overseas Christian groups, and the third a Korean-American pastor accused of espionage for the South.
Following Warmbier's death, the tour group that arranged his trip said it would no longer take Americans into the isolated country.
"Now, the assessment of risk for Americans visiting North Korea has become too high. The way his detention was handled was appalling, and a tragedy like this must never be repeated," said the China-based Young Pioneer Tours.
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Warmbier was on a tourist trip when he was arrested and handed a 15-year sentence in March last year, a punishment US officials decried as out of proportion to his alleged crime.
"It's a total disgrace what happened to Otto," Trump said during an event in the Oval Office. "It should never, ever, be allowed to happen. And frankly if he were brought home sooner, I think the result would have been a lot different."
The young man's father, Fred Warmbier, previously criticized former president Barack Obama's administration for how little he did for their son, saying officials had counseled the family against speaking out to avoid antagonizing the North Korean regime.
"The results speak for themselves," the student's father said last week.
Trump paid tribute to Warmbier's family, with whom he has spoken personally, saying "it's incredible what they have gone through."
- 'Heavy responsibility' -
A day earlier, the president slammed the "brutal regime" in Pyongyang, and said he was determined to "prevent such tragedies from befalling innocent people at the hands of regimes that do not respect the rule of law or basic human decency."
Trump's stern language was echoed by South Korean President Moon Jae-In, who said in an interview ahead of a White House visit next week that North Korea bears responsibility for the student's death.
"We cannot know for sure that North Korea killed Mr Warmbier, but I believe it is quite clear that they have a heavy responsibility in the process that led to his death," Moon told CBS television's "This Morning."
Warmbier's release came amid mounting tensions following a series of missile tests by Pyongyang, in an arms buildup that Washington has dubbed "a clear and present danger to all."
Moon, a center-left politician sworn in last month after a landslide win, favors engagement with the North to bring it to the negotiating table, rather than the hardline stance of his ousted predecessor.
Asked how the Warmbier case would affect his efforts to engage North Korea, Moon added: "I believe we must now have the perception that North Korea is an irrational regime.
"Working with such a country, we must achieve the goal of the complete dismantlement of North Korea's nuclear program."
- 'He was home' -
Kim Jong-Un's regime claimed that Warmbier contracted botulism and fell into a coma soon after being sentenced last year.
Doctors last week said Warmbier had suffered severe neurological injuries, for which tests did not conclusively reveal the cause.
They said Warmbier's condition was probably caused by cardiopulmonary arrest cutting the blood supply to the brain.
The young man was described as being in a state of "unresponsive wakefulness," opening his eyes but showing no signs of understanding language or of being aware of his surroundings.
His family said Monday that he first appeared anguished when he first arrived home, but died "at peace."
"He was home and we believe he could sense that," they added.
The young man's funeral will take place at 9 am (1300 GMT) on Thursday at a high school in Cincinnati, and will be open to the public.
- Risk 'too high' -
US Secretary of State Rex Tillerson warned Monday that Washington holds North Korea "accountable" for Warmbier's fate, and demanded the release of three other Americans held by North Korea.
Two were teachers at a Pyongyang university funded by overseas Christian groups, and the third a Korean-American pastor accused of espionage for the South.
Following Warmbier's death, the tour group that arranged his trip said it would no longer take Americans into the isolated country.
"Now, the assessment of risk for Americans visiting North Korea has become too high. The way his detention was handled was appalling, and a tragedy like this must never be repeated," said the China-based Young Pioneer Tours.
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