Transcript for Battle to save terminally ill baby Charlie Gard has come to an end

Next this evening, the parents of baby Charlie at the center of an international tug of war. They are now signaling the emotional end to their legal battle. It comes after a visit to the American doctor. ABC's James Longman once again from London. Reporter: Through his grief, Charlie's father adamant that treatment could have worked. Our son is an absolute war Yo your, and we'll miss him terribly. Reporter: The experimental treatment offered by an American doctor could have worked. Had Charlie been given the treatment sooner, he would have had the potential to be a Normal little boy. Reporter: But the hospital says his genetic condition was always terminal. Supporters outside court crushed. They have been out here every day chanting their support for the family, but when news started to spread out here, the mood changed. The fight to keep Charlie alive dragging on since March, sympathy swelled around the world, including from the pope and Donald Trump. The judge said dark days lay ahead for Charlie's parents who will now let their son go just short of his first birthday,

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