The parents of Charlie Gard have dropped their application to fly their seriously ill baby to the US for an experimental treatment to save his life, Fox News reported.

11 month old Charlie suffers from a rare mitochondrial disease which has already caused him severe brain damage. His parents, Chris Gard and Connie Yates, have fought a legal battle to bring him to the US to receive experimental therapy which is administered there and to keep him on life support.

However, doctors at the Great Ormond Street Hospital for Children in London, where Charlie is being treated, were allowed by British judges and the European Court for Human Rights to turn off his life support so that he may die peacefully and without further pain.

The denial of the parents' right to attempt to save their child has faced international criticism, including from US President Trump.

Attorney Grant Armstrong said at London's High Court that recent tests showed that the muscular damage Charlie suffered while waiting for the court decision was irreversible.

"It's too late for Charlie," Armstrong said. "The damage has been done."

Charlie's parents cried in the courtroom as Armstrong announced the verdict.

"As Charlie's devoted and loving parents we have decided that it's no longer in Charlie's best interests to pursue treatment and we will let our son go and be with the angels," Chris Gard said in court.

Gard blamed the lengthy court battle for the loss of Charlie's last chance for survival. "Had Charlie been given the treatment sooner he would have had the potential to be a normal, healthy little boy."

"I only wanted to give him a chance at life," Yates said. "We will always know in our hearts that we did the very best for Charlie and I hope that he is proud of us for fighting in his corner."

"We will have to live with the what-ifs which will haunt us for the rest of our lives."