Kanye West's producer 88-Keys has revealed the rapper is collaborating with Bruno Mars.

The 39-year-old music-maker - who has long been a pal of Kanye's - teased the pair of chart-topping stars are finally recording a track together, after the 37-year-old star admitted he was keen to record with the 'Uptown Funk' vocalist earlier in the year.

The producer wrote ''S***'s Ugly! (sic)'' alongside an image on his Instagram account featuring text saying: ''Puff Daddy x 88-Keys x Kanye West x Bruno Mars (sic).''

In a further tweet, believed to be referring to a series of messages posted by Kanye in February, he wrote: ''Label sessions pretty much the entire time. Go look at Kanye's timeline until you see my name just to get an idea of what I'm up to.''

The 'All Day' rapper previously mentioned the producer while apologising to the 'Locked Out of Heaven' singer in two tweets following the Grammy Awards, in which he admitted he ''would love'' for the star to feature on a track, made by himself, 88-Keys and Diddy, who is also known as Puff Daddy.

He wrote at the time: ''I also want to publicly apologise to Bruno Mars, I used to hate on him but I really respect what he does as an artist.

''I also would love for Bruno to sing this hook on this song 88 Keys / Puff and I produced... I even asked Tyler to shoot the vid. (sic)''

Although it is not yet known whether the track will feature on Kanye's forthcoming seventh album 'SWISH', Diddy recently revealed he would also be producing the record.

He said: ''I'm definitely producing on his album, but I don't know how it's going to end up.

''It's up to Kanye and how he sees the album going. But we're definitely working together, producing a lot of records together and having a lot of fun.''