Sir Elton John broke down in tears for 45 minutes when questioning how much time he has left in the world

Elton was recording a new song, 'When This Old World Is Done with Me', when the thought of leaving behind his two sons, Zachary Jackson, 14, and Elijah Joseph, 12, and his husband David Furnish, 62, came into his head, and he began to weep.

He told the 'Smartless' podcast: "I wrote a song at the end of the album and I just get the lyrics, Bernie Taupin's lyrics called 'When This Old World Is Done With Me'.

"And so I'm writing the verse, like, 'Oh, this is really pretty.' And then I get to the chorus and of course it's about my death.

"When you get to my age, which is near 100, you think, 'How much time have I got left?'

"And you've got children, you've got a wonderful husband, you just think about mortality.

"So, when I got to the chorus, I just broke down for 45 minutes and it's all on film."

The tune appears on Elton and fellow musician Brandi Carlile's upcoming collaborative album 'Who Believes in Angels?', which will drop on April 4th.

Brandi thinks everyone should watch the moment Elton breaks down - which features on his documentary 'Elton John: Never Too Late' - because it was a "really human, like deeply flawed and embarrassing," moment.

She added: "I want everybody to see it because it's really human, like deeply flawed and embarrassing.

"And the kind of s*** that you do when you forget that there is a camera on is what's really interesting.

"He got to the end of that chorus and his voice started to shake and I thought, 'Oh, he's going, like he's going to really go.' And he went into a real moment."