The 12-year-old boy’s family want him to be moved to a hospice for his “last moments”.
The family of 12-year-old Archie Battersbee have made a legal bid for permission to move him from the Royal London Hospital to a hospice.
It comes after Wednesday’s European Court of Human Rights (ECHR) decision to refuse an application to delay any changes to his treatment.
Doctors have warned there is “significant risk” in moving him.
Life-sustaining treatment for Archie has been in place since April.
It had been due to be withdrawn on Wednesday but was delayed for the ECHR to consider his family’s appeal.
However, the ECHR said it “would not interfere” with the UK courts’ rulings, paving the way for treatment to be stopped.
Afterwards, Archie’s mother, Hollie Dance, said the legal battle to postpone the withdrawal of her son’s life support was at “the end”.
She said the court’s decision to refuse their application was “another heart-breaking development” and that the family wanted to file an application in the High Court to transfer Archie to a hospice.
Lawyers for Barts Health NHS Trust, which runs the Royal London Hospital, had said in a letter to the family’s legal team that any application to do this would “be opposed on both a procedural basis and best interests basis”.
“The trust continues to put Archie’s welfare and best interests at the forefront of its decision making about his care,” the letter said.
“It believes that Archie’s condition is unstable and that transferring him even a short distance involves significant risk.”
It added the trust considered that the family were now “at the end of the procedural options open to them” and that “any further delay is not in Archie’s best interests”.
On that basis, it intended to withdraw Archie’s treatment at 11:00 BST on Thursday unless an application over the hospice move was submitted by 09:00.
Ms Dance has said she wanted her son “in a peaceful hospice to say goodbye and spend time with his family, uninterrupted by the noise and chaos”.
A spokeswoman for Archie’s family said it was “absolutely disgusting” that the family were “not even allowed to choose where Archie takes his last moments”.
She added that a hospice had said it would take him.
A High Court order made in July requires that Archie remains at the Royal London Hospital while his treatment is withdrawn.
The trust have said changes to Archie’s treatment would not be made until legal issues were resolved.
Archie was found unconscious at home in Southend-on-Sea, Essex, on 7 April. His mother believed he may have been taking part in an online challenge at the time.
Doctors had previously said it was “highly likely” he was brain-stem dead, with no chance of recovery and it was in his best interest for life support to end.
A High Court judge said earlier that continuing treatment was “futile”.
On Wednesday, in the latest in a series of court challenges, Archie’s parents had argued the plan to withdraw treatment and ignore the concerns of a UN committee would breach a range of human rights safeguards, including right to life and right to a fair trial or hearing.
But the ECHR said it “considered the conditions of admissibility…were not fulfilled”.
Court of Appeal judges had previously ruled Archie’s life-sustaining treatment should not continue beyond 12:00 on Tuesday, but this was also delayed for an appeal process which was ultimately unsuccessful.
A previous High Court ruling said “every bodily function [of Archie’s] is now maintained by artificial means”, while another said he had not “regained awareness at any time”.
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