In a press conference following his meeting with Kim Jong-un, the US president hinted that human rights issues had been discussed, and hoped for a united Korea
Otto Warmbier's parents also said their son was 'systematically tortured' and 'injured'
US passport holders will not be allowed to travel to the secretive country following a State Department decision
The 22-year-old student died days after being released from the country in a coma
A defector has said 20 people would be stuffed into each cell in North Korea camps and were often tortured within an inch of their life
Student Otto Warmbier died on Monday after being sent back to the US from North Korea in a coma