Ashya King has been reunited with his parents after his father accused a hospital in England of wanting to "kill his son, turn him into a vegetable" and claimed the couple were "treated like terrorists".
Brett King insists he told Southampton General Hospital, where the five-year-old was receiving treatment, that they were going to travel abroad so Ashya could receive alternative proton beam therapy.
In an emotional press conference in Spain, Mr King said: "They treated us like terrorists. The hospital wanted to kill him, turn him into a vegetable. Would I do it all again? Yes I would."
His comments came before he and his wife Naghmeh travelled to Malaga to see their son in hospital, after being released from prison. On Wednesday afternoon the couple got to see the youngster for the first time since their arrests on Saturday evening.
However they were told that they could not remove Ashya from the hospital without a judge's approval because he remains a ward of court.
Mr King claimed that interventions by David Cameron and the Department of Health had failed to help his cause because he and his wife still "don't have custody".
Earlier he had said of Southampton General Hospital: "The hospital knew I was leaving and going abroad. I told them I was leaving with him. I have no idea why they threatened to put a protection order on him. They wanted to kill our son. What I want them to do now is help them as much as they can as soon as possible. He has not got long to live.
"When I was in my I could hear my wife crying in her cell. I couldn't console her. Our hearts were hurting to see him. Being locked up I couldn't help my son or my wife, I didn't know what the future held, what would happen to Ashya without us.
"They arrested us and took our son without allowing any of us to visit him. My heart is still up here. He needs this therapy immediately. I love my son, without him there is no proper future. He has not got long to live. We want them to help him as soon as possible."
In the press conference Mr King also told of the anguish of hearing his wife crying from his cell in Soto del Real prison near Madrid.
His voice breaking with emotion, he described the couple's desperation to see Ashya because he "hasn't got too many months to live".
Mr King said: "When we were in prison there wasn't a minute that went by without our hearts hurting to see Ashya. My wife spent most of the time crying in the cell.
"I was going to ask to move cells because I was worried and I couldn't listen to my wife crying. When you are locked up you can't do anything."
Before seeing Ashya Mr King described the uncertainty they faced about their son's condition after they were detained.
"What is going to happen to Ashya without us? We didn't know what was happening because they arrested us and directly they took our son away.
"We said 'You don't even really know what's wrong with him. He needs therapy on his legs, on his arms. You need to turn him from side to side.'
"But they're not interested. They just want to take him away from us."
He thanked David Cameron and "anyone who has helped release us"
The proton clinic in Prague has said clinicians there are ready to treat Ashya after receiving the five-year-old's medical notes.
Clinicians there have been in contact with Ashya's specialists at Southampton Hospital, who have agreed to refer him to the clinic after two cycles of chemotherapy in the UK, which is likely to take several weeks.
"We have agreed that proton therapy is a suitable method of treatment for Ashya", said Dr Jiri Kubes, head of proton therapy at Proton Therapy Center Czech.
His parents took Ashya out of the country so he could receive alternative proton beam therapy in the Czech capital.
They will be reunited with their son later today after being released from a Spanish jail following the Crown Prosecution Service's (CPS) decision to drop the case against them.
Mr King says they are "relieved" to be free and are looking forward to seeing their son again.
An international arrest warrant was issued after Mr and Mrs King took Ashya from Southampton General Hospital, where he was being treated for a brain tumour.
They were detained on Saturday near Malaga and taken to Madrid, where they were kept in separate jails, pending an extradition hearing.
The decision by the CPS on Tuesday to take no further action came after Prime Minister David Cameron and Deputy Prime Minister Nick Clegg joined growing calls for the family to be reunited.
Mr Cameron welcomed the news of the Kings' release, saying it was "important this little boy gets treatment and the love of his family".
Sanjay Ganatra, a family friend, told Sky News their release was a "victory for common sense".
He organised a petition calling for their release along with 16-year-old Ethan Dallas, a friend of Ashya's brother Naveed, which attracted almost 200,000 signatures by 5pm on Tuesday.