Is Don McLean about to reveal the full meaning of the lyrics to his signature song American Pie? The 69-year-old is to auction the original manuscript of his iconic 1970s hit, which he says will “divulge” the meaning of the track.

The 16 pages of handwritten and typed drafts, including notes and deletions for the recording, will go on auction at Christie’s in April, where they are tipped to fetch up to $1.5m (£1m).

Although McLean has revealed that the beginning of the eight-minute ballad focuses on the death of singer Buddy Holly, who died in a plane crash in 1959, he has otherwise been evasive about the meaning of the lyrics. This has sparked decades of speculation and theories.

However, he now promises that the manuscript will reveal all. “I wanted to capture, probably before it was ever formulated, a rock’n’roll American dream,” McLean said. “The writing and the lyrics will divulge everything there is to divulge.”

Asked why he is now auctioning the manuscript, he told Rolling Stone: "I'm going to be 70 this year. I have two children and a wife, and none of them seem to have the mercantile instinct. I want to get the best deal that I can for them. It's time."

Lyrical manuscripts have previously raised over a million dollars at auction. Bob Dylan’s lyrics for Like A Rolling Stone sold for just over $2m at auction last year. That broke the record for a handwritten manuscript, previously held by John Lennon’s lyrics for A Day in the Life, which sold for $1.2m.