John Lennon's son sang one of the most famous songs of 'The Beatles'

Julian Lennon performs for the first time a cover of one of the MOST ICONIC songs
Musician's son sang a song that he promised to perform only during the end of the world.

The son of the Beatles star John Lennon — British rock singer Julian Lennon — sang his father's song Imagine, which he promised to perform only when the end of the world comes.

''I had always said, that the only time I would ever consider singing Imagine would be if it was the end of the world,'' wrote he on YouTube along with a video of his performance.

Imagine was originally released on John Lennon's 1971 album of the same name, per Daily Mail.

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