Interference from the Vatican and Donald Trump in the case of Charlie Gard is "extremely unhelpful and very cruel", Professor Robert Winston has said.

His comments came after the US president and the Pope tweeted their support for the boy, who has been at the centre of a lengthy legal battle involving his parents and doctors at Great Ormond Street Hospital (GOSH).

The Vatican's paediatric hospital stepped in to offer care after Pope Francis called for Charlie's parents, Chris Gard and Connie Yates, to be allowed to "accompany and treat their child until the end".