Pharrell's Happy originally recorded by Cee Lo Green

Pharrell and Cee Lo Green

Pharrell Williams has revealed that his number one single Happy was originally recorded by Cee Lo Green.

The "powers that be" apparently turned down Green's version of the song, saying the future worldwide hit "wasn't a fit" for their client.

"[Cee Lo] wanted to do it ... [and] he did do it," Williams explained in a US radio interview after being asked if he'd heard anyone else was singing it.

"He sounded amazing on it. I mean, he burns my version," he added.

I can't believe it's [Happy] become what it has
Pharrell Williams

"Some folks on his team just felt that the priority should be on [Cee Lo's] album at the time, so they elected not to do that song."

Happy became the lead single taken from Williams' new solo album, Girl, having appeared on the soundtrack to Despicable Me 2.

Since its release in November the track has sold more than 1.3m copies in the UK, topping the Official Singles Chart on three separate occasions.

"I can't believe it's [Happy] become what it has," he said in the interview.

Image caption Beyonce's Pretty Hurts could have been sung by Rihanna or Katy Perry

Songs being rejected by one artist and recorded by another is not uncommon in the music world.

Beyonce's Pretty Hurts was offered to Rihanna and Katy Perry before the Crazy in Love singer secured the track and's Scream and Shout was originally meant for former N-Dubz singer Tulisa rather than Britney Spears.

Here are some other examples of tracks that ended up being sung by different artists than they were first intended for.

Justin Timberlake - Rock Your Body

Justin Timberlake and Michael Jackson

Pharrell wrote eight songs for Michael Jackson, which ended up on Justin Timberlake's debut solo album Justified.

Talking about the tracks, Pharrell said: "I think he heard too much of himself in it and it wasn't challenging for him."

Rihanna and Calvin Harris - We Found Love

Rihanna and Nicole Scherzinger

Nicole Scherzinger revealed in an interview with Notion Magazine that she had the opportunity to record We Found Love.

"I passed on We Found Love," Scherzinger admitted. "I've got the demo of that song and I was busy at the time."

Coldplay - Paradise

Chris Martin
Image caption Coldplay will headline Radio 1's Big Weekend 2014 in Glasgow

In a recent interview with BBC Radio 1's Zane Lowe, Chris Martin said the track was originally going to be released as an X Factor winner's single.

He then added that when other band members heard the track they decided to keep it as their own.

Lady Gaga ft Beyonce - Telephone

Lady Gaga and Britney Spears

The Applause singer's 2009 number one single was originally recorded by Britney Spears.

A demo featuring Spears' vocal leaked in 2010.

David Guetta - Titanium ft Sia Furler

David Guetta

The vocal on the UK number one single is that of the songwriter Sia Furler, who claims to have thought she was writing a song for him to give to Alicia Keys.

The French DJ tried to invite other hit singers to replace Sia's demo vocal, including Mary J. Blige, but it was Katy Perry who advised him to leave it as it was.

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