The parents of a 12-year-old boy, who doctors have said is showing “no signs of life”, have been granted a further 24 hours to appeal against a decision to end his life support treatment. The extension is to enable Archie Battersbee’s parents to make an application to the European court of human rights (ECHR) but they said their preferred option is to take the case to the United Nations convention on the rights of people with disabilities (UNCRPD). On Monday, three judges, sitting at the court of appeal, refused an application against a high court decision that doctors at the Royal London hospital, in east London, could stop treating Archie – but agreed to stay the effect of their judgment until 2pm on Wednesday. A written application to the court of appeal on Wednesday extended the stay until 2pm on Thursday. The Christian Legal Centre, a campaign group that is supporting Archie’s parents, said this is not enough time to allow them to go to the UNCRPD, which it believes is more likely than the ECHR to order that the withdrawal of life support be delayed while a complaint is being investigated. It said the ECHR “has a track record of rejecting applications from parents in end-of-life cases”. Archie’s mother, Hollie Dance, 46 said: “It feels wrong that the court of appeal have tried to force us down a road which they know will fail and have taken away our rights of taking the case to the UN. “All we have asked for from the beginning is for Archie to be given more time and for Archie’s wishes and ours to be respected. As long as Archie is alive, I will never give up on him, he is too good to give up on.” Dance and Archie’s father, Paul Battersbee, 57, want Archie to die a “natural” death. Their son sustained brain damage about three months ago when, his mother believes, he choked while taking part in a viral social media trend. The centre suggested Archie’s parents would attempt to launch an appeal to the supreme court on Thursday to allow them to make their case to the UN. The stay granted is specifically to allow for an application to the ECHR but the Guardian understands there is nothing preventing them from making an application to the UNCPRD. The extension was granted because of the illness of Archie’s father, who was has been discharged from hospital after being admitted on Monday morning with a suspected heart attack before the court of appeal hearing.