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Life-sustaining treatment for the 12-year-old has been in place since April and was due to be withdrawn earlier.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