The European Court of Human Rights (ECHR) authorized on 27 June the end of the baby's survival, following the British court which had previously allowed the end of the artificial ventilation of the child. The hospital will remove Charlie Gard from a life support machine against his parents' wishes. London's Great Ormond Street Hospital, which earlier turned down the parents' plea to move Charlie to the USA, has now refused a Vatican hospital's request to transfer the child to Rome for further treatment.
Their talks are likely to be dominated by the North Korea missile crisis and a post-Brexit trade deal, but Number 10 was said to be compiling a detailed briefing on Charlie's case in anticipation of questions from Mr Trump. Italian Foreign Minister Angelino Alfano raised the offer from the Bambino Gesu children's hospital in his call with Johnson.
His story has gone global after his parents Connie Yates and Chris Gard, from west London, were blocked from taking him to the USA for experimental treatment to improve brain function. It meant a child like Charlie could not see, hear, cry or swallow, and needed help to breathe.
The Vatican said that the Pope was following the case "with affection and sadness" and "expresses his closeness to his [Charlie's] parents".
"It's an unimaginable position for anybody to be in", May told Parliament when asked about Charlie Gard, widely known as Baby Charlie, who suffers from a rare condition that causes progressive muscle weakness and brain damage.
Helen Aguirre Ferre, director of media affairs at the White House, said that, "upon learning of" Charlie's case, the president "offered to help the family in this heartbreaking situation". A statement added: 'For them he prays, hoping that their desire to accompany and care for their own child to the end is not ignored'.
Charlie's mother has since told the Daily Mail that the support "has given us hope".
Meanwhile, British Prime Minister Theresa May supports the court ruling, stating her support for the opinions of the doctors at Great Ormond Street, where Gard is being held, who say it's time to remove his life-support and allow him to die.