Hitmaker Pharrell Williams has revealed that 'Happy' wasn't originally intended to be his song.

Speaking exclusively to DJ Howard Stern, Williams admitted that he initially offered his hit single 'Happy' to CeeLo Green, but the 'Forget You' star's team didn't want him to record it because he was working on an album and they were concerned it would sidetrack his progress:

"[I approached] CeeLo for this song. He did it. How do I put this diplomatically... the powers that be did not see it fit for him at the time. There was a much bigger agenda for him - he had bigger fish to fry. He had an album to put out."

He went onto add that there are no hard feelings between them following the incredible success of 'Happy': "He was one of the most gracious people about it. When it came out he congratulated me. He's a super stand-up guy and I love working with him. In fact I have a song with him on his next album. He's a tremendous talent."

Earlier this month, Williams confirmed that the video for 'Happy' has now had over 200,000,000 views and he tweeted: "Thank you Gru for inspiring me to act like you in my Happy video. We just hit 200 million views! @DespicableMe."

Watch Williams talking about the song here: