The 12-year-old’s life support was due to be withdrawn on Wednesday morning.
The European Court of Human Rights (ECHR) has refused an application from Archie Battersbee’s parents to postpone the withdrawal of his life support.
Life-sustaining treatment for the 12-year-old has been in place since April and was due to be withdrawn earlier.
The family applied to the the ECHR after an appeal against the decision to end treatment was refused by the Supreme Court on Tuesday.
But the ECHR said it “would not interfere” with the UK courts’ rulings.
Archie’s mother Hollie Dance said the court’s decision was “another heart-breaking development”.
The 12-year-old was found unconscious at home in Southend-on-Sea, Essex, on 7 April – his mother believes he may have been taking part in an online challenge at the time.
Barts NHS Health Trust, which runs the Royal London Hospital where Archie has been cared for since April, said changes to his treatment would not be made until legal issues were resolved.
Doctors 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 previously said continuing treatment was “futile”.
‘Fight to the end’
The ECHR ruling said it would not grant an interim measure to continue treatment and declared Archie’s parents’ complaints “inadmissible”.
The court would only grant such requests “on an exceptional basis” and “when the applicants would otherwise face a real risk of irreversible harm”, it added.
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”.
Following the ECHR ruling, Ms Dance said: “The NHS, the government and the courts in this country and Europe may have given up on treating him, but we have not.
“We will fight to the end for Archie’s right to live.”
Ms Dance said she had received offers to care for her son from health providers in two other countries – Japan and Italy.
“If this country can’t treat him or they’re not willing to treat him, where is the harm in allowing him to go to another country?” she said.
But Prof Alastair Sutcliffe, Professor of General Paediatrics at UCL, said: “The UK is a world leader in health care and indeed the research behind therapies.
“I am confident no stone has been unturned with regards to treatment, and evidently there is not one. Alas.”
Before the ECHR ruling was announced, Alistair Chesser, chief medical officer for Barts Health NHS Trust, said: “Our deepest sympathies remain with Archie’s family and we aim to provide the best possible support to everyone at this difficult time.
“As directed by the courts, we will work with the family to prepare for the withdrawal of treatment, but we will make no changes to Archie’s care until the outstanding legal issues are resolved.”
Court of Appeal judges had previously ruled his life-sustaining treatment should not continue beyond 12:00 on Tuesday.
But this was delayed while the Supreme Court heard an appeal application from Archie’s parents.
The family had asked that court to assess whether more time should be given for the United Nations Committee on the Rights of Persons with Disabilities to look at the case.
But it said the Court of Appeal had “made the correct decision”.
A previous High Court ruling heard “every bodily function [of Archie’s] is now maintained by artificial means”, while another heard he had not “regained awareness at any time”.
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