London court reopens Charlie Gard case for 'new evidence'

The parents of 11-month-old Charlie Gard have been granted a second chance to prove in courts their son can be saved by treatment outside of the UK.

This is an undated hand out photo of Charlie Gard provided by his family. Source: AAP

A British court has given the British parents of 11-month-old Charlie Gard a chance to present fresh evidence that their terminally ill son should receive experimental treatment.

Judge Nicholas Francis gave the couple until Wednesday afternoon to present the evidence and set a new hearing for Thursday.

The re-opening of the case at London's High Court may allow Charlie to receive the therapy treatment at his current hospital or abroad.

Great Ormond Street Hospital, which had intended to turn off the baby's life support systems, applied for the court hearing because of "new evidence relating to potential treatment for his condition".

The evidence came from researchers at the Vatican's children's hospital and another facility outside of Britain.

The application came after both Pope Francis and President Donald Trump fuelled international attention to the case, with hospitals in Rome and the US offering to provide Charlie the experimental therapy.

Previous court rulings have said that Charlie couldn't receive the treatment for his mitochondrial depletion syndrome, a rare genetic disease that left him with brain damage and unable to breathe unaided, and that he should be taken off of life support.

British and European courts sided with the hospital's original stance that the experimental treatment was "unjustified" and might cause Charlie more suffering with no cure.

The judge insisted there had to be "new and powerful" evidence to reverse earlier rulings barring Charlie from travelling abroad for treatment.

But he rejected an attempt by the child's parents to have another judge hear the case.

Charlie's parents were overcome with emotion during the hearing. At one point, the baby's father, Chris Gard ,yelled at a barrister representing the hospital: "When are you going to start telling the truth?"

A petition supporting Charlie's right to treatment has garnered around 350,000 signatures and more than STG1.3 million ($A2.2 million) pounds have been raised online for his case.