While regulatory approval has been known to halt a merger in its tracks, a $35 billion pending acquisition that could have resulted in the largest advertising agency on the planet has been scrapped for decidedly more personal reasons. U.S.-based advertising giant Omnicom and its French counterpart Publicis have tossed out a deal announced last July, primarily due to internal cultural clashes and power struggles within the forthcoming entity’s executive suites, Reuters reports.

The $35-billion merger of U.S.-based Omnicom and France’s Publicis collapsed on Friday after a battle for control destroyed plans to create the world’s largest advertising agency. The deal, heralded in July as a merger of equals that would enable the two agencies to compete more effectively in the digital arena, foundered on issues ranging from its complex tax structure to the firms’ divergent cultures. The two sides were also losing major work – more than $1.5 billion in the past month alone – and did not want to let the uncertainty continue. “I have not been able to convince John that balance is balance,” Publicis Chief Executive Maurice Levy said of his Omnicom counterpart, John Wren.