Rapper 50 Cent's former friendship with boxer floyd mayweather, Jr. has turned into a nasty grudge match over a business deal gone wrong.

The former partners fell out when plans to set up a fight promotion company fell flat and now 50, real name Curtis Jackson, has teamed up with the champion's bitter rival Manny Pacquaio.

Announcing he had severed all ties with Mayweather, Jr. last week (ends02Dec12), the rap star claimed his former partner had failed to honour an agreement to fund the original joint venture.

In a series of Twitter.com posts, the angry hip-hop mogul wrote, "Tmt Is Over the money team is no longer a team... I'm no longer apart or down with Tmt promotions... cause the other half of the money team Didnt put up there $Money$ (sic)."

50 and the boxer have since traded insults over Twitter.com and over the weekend (03-04Nov12), Mayweather, Jr. took aim at his ex-business partner's lack of success as a rapper.

He wrote, "Men lie... women lie numbers don't lie. Wayne, Drake, Rick Ross, Kanye please help this boy."

Mayweather, Jr. linked the tweet to a chart featuring 50 Cent's declining album sales in recent years.

The boxer also chided the rapper, calling him "A male boxing groupie..." and adding, "hold my belts because your album sales have declined."

50 Cent responded by insisting, "Money Floyd you know I have more Money then you (sic)... you go broke every fight stupid."

And the feud could be settled in the ring - 50 Cent is keen to set his own boxer, undefeated Cuban Yuriorkis Gamboa, up with a big-cash fight against Mayweather, Jr.

The rap star writes, "Gamboa Is Mad Floyd. He gonna beat ya a** man. He (is) moving up in weight."