Sir Tom Jones has explained that he can’t afford to lose his temper on the The Voice UK as he fears it is could jeopardise his health.

The Delilah singer has been criticised for looking half asleep in his new TV coaching role, but Jones insists that his docile state is best for everyone.

Speaking to the Radio Times he said: “I have a temper that frightens me. When I was younger I got into fights. Now I’m older, I can’t get into any bother. Some people explode and are cool again within five minutes. I can’t be like that.

“Now if I explode, I’m the one who’s going to die. I’m an old man. I’m happy and everything’s great, so leave me alone.”

Jones also stated that he is refusing to dye his silver hair for the talent show saying: “To each to his own. It’s not for me to tell others what to do. But you can’t get to a certain age and have black hair. If some can, bless ‘em.”

He added: “Every Christmas, I’d take two months off and never dye my hair. And when I started a new tour, I’d think, 'It’s not white enough, a bit patchy,' so I’d dye it again. It must have looked pretty obvious. I should have let it go five years earlier.”