Harry Potter star Sir Michael Gambon is heartbroken after quitting theatre due to his diminishing memory.

The veteran actor, who played Albus Dumbledore in the magic franchise, struggles with his short-term memory, and is no longer able to memorise scripts even though he has been cleared by doctors who tested him for Alzheimer's disease.

He attempted to bypass the problem by having lines fed to him through an earpiece, but Gambon admits the scheme did not work and he has now decided to walk away from theatre for good.

He tells Britain's The Sunday Times Magazine, "It's a horrible thing to admit but I can't do it. It breaks my heart... It's when the script's in front of me and it takes me forever to learn it. It's frightening.

"There was a girl in the wings and I had a plug in my ear so she could read me the lines and after about an hour I thought, 'This can't work. You can't be in theatre, free on stage shouting and screaming and running around, with someone reading you your lines'."

Gambon, 74, plans to continue working in both film and Tv.

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