R&B singer R Kelly has sued rapper Jay-Z for $75m (£50m) after Kelly was kicked off their joint US tour.
Jay-Z (left) and R Kelly were in the middle of their joint tour
Kelly said he was attacked with pepper spray by a member of Jay-Z's entourage at a New York gig on Saturday.
Kelly is suing for breach of contract, alleging Jay-Z's "spite and jealousy" forced him off the tour.
A statement from Island Def Jam Records, Jay-Z's label, blamed Kelly's "lack of professionalism and unpredictable behaviour".
The tour was supposed to be "the perfect marriage of hip-hop and R&B - instead, it's going to be a terrible divorce", said Kelly's lawyer Edward Hayes.
Jay-Z's publicist denied the rapper or his associates were involved in the alleged pepper spray incident.
Court papers filed by Kelly said the animosity led to deliberate technical problems, violence against Kelly and threats to force the promoter to drop him.
They also hint at tension between the two stars over the split in profits - Kelly had a 60% share of the first $15m (£8.2m) earned, compared with Jay-Z's 40%.
Kelly was fired by the tour's promoter, Atlanta Worldwide Touring, also named as a defendant.
The 40-city tour was subsequently cancelled.
Kelly said in his court papers he was performing on Friday when he noticed two men in the audience open their coats and display dark objects he thought might have been guns.
He said he left the stage twice but returned after police arrived and found nothing - and claims he was pepper-sprayed shortly afterwards.