Actress Melissa Joan Hart has led tributes to British boy Charlie Gard, who has died at 11 months old.

His death on Friday came days ahead of his first birthday, following a legal battle between his parents and Great Ormond Street Hospital (GOSH).

The case of the youngster, who had a rare genetic condition, gripped the attention of people across the globe, including the US actress, who said she was “heartbroken” by the news and shared her “prayers” for the family.

I'm absolutely heartbroken for Charlie Gard and his family and we are praying for their peace in knowing that their baby boy is now part of the army of tiny angels playing on swings in the giant playground up above. It's terrifying that a government can tell parents if their child should live or die. #unfair 💔💔💔 #Repost @charliesfight ・・・ It’s with great sadness that we have to inform you that Charlie passed away earlier this afternoon. Connie has released a brief statement: ‘Our beautiful, little boy has gone. We are so proud of you, Charlie.’ We ask that everyone respects the family’s privacy at this difficult time, but we would all like to say a huge thank you to everyone for your continued support. 💙💙💙

A post shared by Melissa Joan Hart (@melissajoanhart) on

In a post on Instagram, the mother of three criticised a UK High Court judge’s approval of a plan to see Charlie moved to a hospice and have his life support withdrawn.

She wrote: “I’m absolutely heartbroken for Charlie Gard and his family and we are praying for their peace in knowing that their baby boy is now part of the army of tiny angels playing on swings in the giant playground up above.

“It’s terrifying that a government can tell parents if their child should live or die. #unfair #Repost @charliesfight”.

Best known for playing the high school witch in teen comedy Sabrina, 41-year-old Hart is an active campaigner for children’s charities and has founded her own clothing line, which donates proceeds to a number of organisations.