Yoko Ono is to receive a songwriting credit on John Lennon's 'Imagine'.

The 1971 classic was the best-selling single of the Beatles legend's solo career and his widow was one the main inspirations and influences behind it.

The song was awarded the National Music Publishers Association Centennial Song Award at a ceremony in New York on Wednesday (14.06.17) where it was revealed that the 84-year-old musician, who was in a wheelchair pushed by her son Sean Lennon at the event, would be added to the list of contributors.

NMPA's CEO David Israelite said on stage: ''While things may have been different in 1971, today I am glad to say things have changed. So tonight, it is my distinct honour to correct the record some 48 years later, and recognise Yoko Ono as a co-writer of the NMPA Centennial Song 'Imagine' and to present Yoko Ono with this well-deserved credit.''

A video message from 1981 from John - who was shot dead by Mark David Chapman in the archway of the Dakota, his residence in New York City on December 8, 1980 - was aired at the bash, in which he said Yoko was deserving of a co-writing credit because of the ''influence and inspiration'' she provided for the lyrical content.

Sean, 41, later took to Instagram to declare it the ''proudest day of his life'' when it was announced his mum would receive the credit.

He said his mother was overcome with emotion and burst into tears of joy and to top it off Patti and Jesse Smith then performed their own rendition of the track.

Sharing a picture with his mother, 70-year-old Patti and her daughter, he wrote: ''Proudest day of my life: The National Music Publishers Association just gave the centennial (song of the century) award to Imagine, but WAIT! Surprise! They played an audio interview of my father saying (approximately) 'Imagine should've been credited as a Lennon/Ono song, if it had been anyone other than my wife I would've given them credit.' Cut to: my mother welling up in tears, and then Patti and Jesse Smith played Imagine! Patience is a virtue! (PS they officially declared Imagine to be a Lennon/Ono song and gave my mother a second award! (sic)''